User:John R. Brews/Sample: Difference between revisions

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==Liénard–Wiechert potentials==
''See also'' [[Help:Index/Formatting/References]]
<br/>
{{TOC|right}}
{{TOC|right}}
The '''Liénard–Wiechert potentials''' are scalar and vector potentials that allow determination of exact solutions of the [[Maxwell equations]] for the [[electric field]] and [[magnetic flux density]] generated at an arbitrary location by an ideal point charge moving in a trajectory prescribed in advance (not calculated from any dynamical model). Because the trajectory is prescribed in advance, no account is taken of effects upon the charge motion due to its radiation of energy and momentum.
'''List-defined references''' (LDR) is a referencing method that moves the text of the references out of the main body of an article and into the ''References'' section at the bottom of the article.  


==Mathematical results==
LDR is a way to make referencing of article contents with a great deal less cluttering of the article's main body text in the edit page. Reduced clutter makes reading and revising text in the edit page much easier, and it also makes it possible to edit all the citations directly in the ''References'' section, instead of searching for them individually through the text. Creating LDR is not only cleaner than previous methods such as the [[Help:Index/Formatting/References|<nowiki><ref>-</ref></nowiki> method]], it is a method that will be more easily understood by new users.  
Define '''''&beta;''''' in terms of the velocity '''''v''''' of a point charge at time ''t'' as:
:<math>\boldsymbol \beta =\boldsymbol v /c_0 \ , </math>
and unit vector '''û''' as
:<math>\mathbf{\hat u } = \frac{\boldsymbol R}{R} \ , </math>
where '''''R''''' is the vector joining the observation point ''P'' to the moving charge ''q'' at the time of observation, ''c<sub>0</sub>'' the [[speed of light]] in [[classical vacuum]]. Then the ''Liénard–Wiechert potentials'' consist of a scalar potential ''&Phi;'' and a vector potential '''''A'''''. The scalar potential is:<ref name=Melia/>


:<math>\Phi(\boldsymbol r , \ t)  =\left. \frac{q}{4\pi \varepsilon_0 }\frac{1}{(1-\mathbf{\hat u \cdot }\boldsymbol v )R}\right|_{\tilde t} \ , </math>
==Overview of how LDR works==
where the tilde {{nowrap|‘ '''<sup>~</sup>''' ’}} denotes evaluation at the ''retarded time'' ,


:<math>\tilde t = t - \frac{|\boldsymbol r - \boldsymbol r_0(\tilde t)|}{c_0} \ , </math>
This section explains the steps and coding to be used in the '''''edit page''''' of a Citizendium article in order to cite references as the sources for words or statements (sentences or paragraphs) in the main body of the article.


''c<sub>0</sub>'' being the [[speed of light]]  in [[classical vacuum]], '''''r''''' the location of the observation point, and  '''''r<sub>O</sub>'''''  being the location of the particle on its trajectory. The symbol ''&epsilon;<sub>0<sub>'' is the [[electric constant]] of the [[SI units]].
The user creates a short unique ''<font color=green>id</font>'' (identifier or name) for each individual reference which is formatted like this:
:<font color=green><nowiki><ref name=id/></nowiki></font> &nbsp; Note the forward slash (&thinsp;<font color=green>/</font>&thinsp;) at the end of the ''<font color=green>id</font>''.


The vector potential is:
The ''<font color=green>id</font>'' is arbitrary, but must be one word, and cannot include punctuation marks or letters like ''à'' with diacritical marks.
:<math>\boldsymbol A(\boldsymbol r , \ t) =\left.\frac{q \mu_0}{4\pi} \frac{ \boldsymbol v}{(1-\mathbf{\hat u \cdot }\boldsymbol \beta )R}\right|_{\tilde t} \ . </math>


The symbol ''&mu;<sub>0<sub>'' is the [[magnetic constant]] of the [[SI units]].With these potentials the electric field and the magnetic flux density are found to be (dots over symbols are time derivatives):<ref name=Melia/><ref name=Muller/><ref name=Oughstun/>
To cite a reference in the main body of the article, the user places <font color=green><nowiki><ref name=id/></nowiki></font> for that reference immediately to the right of the statement. The same insertion may be used in multiple locations in an article however many times that reference is needed.


:<math>\boldsymbol E ( \boldsymbol r , \ t) = -\boldsymbol \nabla \Phi -\frac{\partial}{\partial t} \boldsymbol A = \frac{q}{4\pi \varepsilon_0} \left[ \frac{
Then in the ''References'' section at the bottom of the article, the user lists each reference formatted like this:


(\mathbf{\hat u}-\boldsymbol \beta )(1-\beta^2)
:<font color=green><nowiki><ref name=id>xxxx</ref></nowiki></font> &nbsp;Where ''xxxx'' is the reference's full description. Quotation marks enclosing the ''<font color=green>id</font>'' are '''''not''''' needed.


}{(1-\mathbf{\hat u} \mathbf{\cdot} \boldsymbol \beta )^3 R^2} + \frac{\mathbf{\hat u \ \mathbf{\times} \ } [(\hat\mathbf u-\boldsymbol \beta )\ \mathbf{\times} \ \boldsymbol {\dot \beta} ]}{c_0(1-\mathbf{\hat u \cdot}\boldsymbol \beta )^3 R} \right ]_{\tilde t} 
Note that the forward slash (&thinsp;<font color=green>/</font>&thinsp;) is '''''not''''' included after the ''<font color=green>id</font>'' in the ''References'' section.
</math>


:<math>\boldsymbol B(\boldsymbol r , \ t) = \boldsymbol \nabla \ \mathbf \times \ \boldsymbol A= \boldsymbol {\hat u \ \times}\ \boldsymbol E/{c_0} \ . </math>
===Some rules===


If the particle does not accelerate, the first term alone survives and for velocities much less than the speed of light the result is the [[Biot-Savart law]]. If the particle accelerates, the last term is called the ''radiation field''. The Biot-Savart term drops off more quickly with distance, and is called the ''near field'' term.  The radiation field drops off more slowly with distance, so it dominates the result at large distances and is called the ''far field'' term.
*Where the user wants to locate a reference for text that is followed by punctuation like a period or a comma, the insertion <font color=green><nowiki><ref name=id/></nowiki></font> should be located immediately to the right of that punctuation, and should be separated from the next word or next sentence by a single blank character space.


==Notes==
*In the ''References'' section, a blank line space '''must''' be provided between each listed reference.
 
*Note that the list in the ''References'' section is within a template. The list '''must''' start with <font color=green><nowiki>{{reflist|refs=</nowiki></font> and it '''must''' end with <font color=green><nowiki>}}</nowiki></font> exactly as shown in the example coding below.
 
===Putting it together===
To summarize, the basic templates used for bibliographic information are the same {{tl|cite book}}, {{tl|cite journal}}  and {{tl|cite web}}  templates used with the <nowiki><ref>-</ref></nowiki> method.<ref name=template  group=Notes/> However, these templates are placed ''not'' in the text, but at the end of the article following a ''References'' header using {{tl|reflist}} and the format:
 
:<font color=green><nowiki>{{reflist|refs=</nowiki></font> &emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;(notice the vertical separator and <font color=green>refs=</font>)
 
:<font color=green><nowiki><ref name=Ref1> {{cite book ...}} </ref></nowiki></font>&emsp; (this is first reference)
 
:<font color=green><nowiki><ref name=Ref2> {{cite book ...}} </ref></nowiki></font>&emsp; (this is second reference, <u>separated by a space</u>)
 
:<font color=green><nowiki>}}</nowiki></font>&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;&emsp;(these are additional final braces)
 
where the names "Ref1", "Ref2" are arbitrary creations of the writer. Connection to these definitions from the text is done with an insertion, such as <font color=green><nowiki><ref name=Ref1/></nowiki></font>, but notice, with a forward slash.
 
Although not necessary to its functionality, for ease in editing, the list of named notes in the ''References'' section can be put in alphabetical order. That makes finding the note in this list easier in the event the note should be edited, for example to update a link or add to descriptive material.
 
==Example==
 
'''''This is how to code the edit page of an article using "List-Defined References"&thinsp;:'''''
:{|cellpadding=8 align=center style="background:#fffaf5; width:99%; border:1px dotted; margin:5px;"
 
|The '''Sun''' is the dwarf star<font color=green><nowiki><ref name=Weissman2007p71/></nowiki></font> at the center of the Solar System. There are eight major planets and other celestial bodies orbiting it.<font color=green><nowiki><ref name=Weissman2007p3/></nowiki></font> It is extremely hot, with surface temperatures in excess of 6,000 K and a central core temperature of about 15,700,000 K.<font color=green><nowiki><ref name=Weissman2007p72/></nowiki></font>
 
Since the Sun is about 150,000,000 kilometers away,<font color=green><nowiki><ref name=Weissman2007p72/></nowiki></font> only a very small amount of its heat and light reach the Earth. By contrast, the Earth's Moon is very much smaller and very much colder.<font color=green><nowiki><ref name=Vasavada1999/></nowiki></font>
 
<nowiki>==References==</nowiki>
 
<font color=green><nowiki>{{reflist|refs=</nowiki></font>
 
<font color=green><nowiki><ref name=Vasavada1999>{{</nowiki></font> cite journal | author=Ashwin R. Vasavadaa, David A. Paige and Stephen E. Wood | title= Near-Surface Temperatures on Mercury and the Moon and the Stability of Polar Ice Deposits | journal= Icarus | volume=141 | issue=2 |pages=pp. 179-193 | date= October 1999 |doi=10.1006/icar.1999.6175 <font color=green><nowiki>}}</ref></nowiki></font><br/>
 
<font color=green><nowiki><ref name=Weissman2007p3>{{</nowiki></font> cite book | author=Paul R Weissman |url=http://books.google.com/books?id=G7UtYkLQoYoC&pg=PA3 | title=Encyclopedia of the solar system |chapter=Chapter 1: The solar system and its place in the galaxy| edition= 2nd Edition |editor=Lucy-Ann McFadden, Paul Robert Weissman, Torrence V. Johnson, editors | publisher=Academic Press | year=2007 | pages= pp. 3 ''ff'' |isbn= 0120885891 <font color=green><nowiki>}}</ref></nowiki></font>
 
<font color=green><nowiki><ref name=Weissman2007p71>{{</nowiki></font> cite book | author=Markus J Aschwanden |url=http://books.google.com/books?id=G7UtYkLQoYoC&pg=PA71 | title=Encyclopedia of the solar system |chapter=Chapter 4: The Sun | edition= 2nd Edition |editor=Lucy-Ann McFadden, Paul Robert Weissman, Torrence V. Johnson, editors | publisher=Academic Press | year=2007 | pages= pp. 71 ''ff'' | isbn= 0120885891 <font color=green><nowiki>}}</ref></nowiki></font>
 
<font color=green><nowiki><ref name=Weissman2007p72>{{</nowiki></font> cite book | author=Markus J Aschwanden |url=http://books.google.com/books?id=G7UtYkLQoYoC&pg=PA72 | title=Encyclopedia of the solar system |chapter=Table 1: Basic physical properties of the sun | edition= 2nd Edition |editor=Lucy-Ann McFadden, Paul Robert Weissman, Torrence V. Johnson, editors | publisher=Academic Press | year=2007 | pages= p. 72 | isbn= 0120885891 <font color=green><nowiki>}}</ref></nowiki>
 
}}</font>
 
|}


{{reflist2|
refs=


<ref name=Melia>
'''''This is what the above coding produces on the article page&thinsp;:'''''


{{cite book |title=Electrodynamics |author=Fulvio Melia |url=http://books.google.com/books?id=xzJLe9UOggEC&pg=PA101 |pages=pp. 101 |chapter=§4.6.1 Point currents and Liénard-Wiechert potentials |isbn=0226519570 |year=2001 |publisher=University of Chicago Press}}
:{|cellpadding=8 align=center style="background:#fffaf5; width:99%; border:1px dotted; margin:5px;"


</ref>
|The '''Sun''' is the dwarf star<ref name=Weissman2007p71/> at the center of the Solar System. There are eight major planets and other celestial bodies orbiting it.<ref name=Weissman2007p3/> It is extremely hot, with surface temperatures in excess of 6,000 K and a central core temperature of about 15,700,000 K.<ref name=Weissman2007p72/>


<ref name=Muller>
Since the Sun is about 150,000,000 kilometers away,<ref name=Weissman2007p72/> only a very small amount of its heat and light reach the Earth. By contrast, the Earth's Moon is very much smaller and very much colder.<ref name=Vasavada1999/>


{{cite book |url=http://books.google.com/books?id=LAgKcg9WexEC&pg=PA223 |pages=p. 223 |title=Electrodynamics: an introduction including quantum effects |author=Harald J. W. Müller-Kirsten |isbn=9812388087 |year=2004 |publisher=World Scientific}}
'''<big>References</big>'''


</ref>
{{reflist|refs=


<ref name=Vasavada1999>{{cite journal | author=Ashwin R. Vasavadaa, David A. Paige and Stephen E. Wood | title= Near-Surface Temperatures on Mercury and the Moon and the Stability of Polar Ice Deposits | journal= Icarus | volume=141 | issue=2 |pages=pp. 179-193 | date= October 1999 |doi=10.1006/icar.1999.6175}}</ref>


<ref name=Oughstun>
<ref name=Weissman2007p3>{{cite book | author=Paul R Weissman |url=http://books.google.com/books?id=G7UtYkLQoYoC&pg=PA3 | title=Encyclopedia of the solar system |chapter=Chapter 1: The solar system and its place in the galaxy| edition= 2nd Edition |editor=Lucy-Ann McFadden, Paul Robert Weissman, Torrence V. Johnson, editors | publisher=Academic Press | year=2007 | pages= pp. 3 ''ff'' | isbn= 0120885891}}</ref>


{{cite book |title=Electromagnetic and optical pulse propagation |author=Kurt Edmund Oughstun |url=http://books.google.com/books?id=behRnNRiueAC&pg=PA134 |pages=p. 134 |chapter=§3.3.2: The field produced by a moving charged particle |isbn=038734599X |year=2006 |publisher=Springer}}
<ref name=Weissman2007p71>{{cite book | author=Markus J Aschwanden |url=http://books.google.com/books?id=G7UtYkLQoYoC&pg=PA71 | title=Encyclopedia of the solar system |chapter=Chapter 4: The Sun | edition= 2nd Edition |editor=Lucy-Ann McFadden, Paul Robert Weissman, Torrence V. Johnson, editors | publisher=Academic Press | year=2007 | pages= pp. 71 ''ff'' | isbn= 0120885891}}</ref>


</ref>
<ref name=Weissman2007p72>{{cite book | author=Markus J Aschwanden |url=http://books.google.com/books?id=G7UtYkLQoYoC&pg=PA72 | title=Encyclopedia of the solar system |chapter=Table 1: Basic physical properties of the sun | edition= 2nd Edition |editor=Lucy-Ann McFadden, Paul Robert Weissman, Torrence V. Johnson, editors | publisher=Academic Press | year=2007 | pages= p. 72 | isbn= 0120885891}}</ref>


}}
}}
|}
Additional examples can be seen in the article [[Set (mathematics)]], which is formatted using the ''CZ:List-defined references'' methodology. The article [[Coriolis force]] also is formatted using the ''CZ:List-defined references'' method, but using the template {{tl|reflist2}}, which works in exactly the same way, but results in a two-column format for the reference listing.
===A style note===


[http://books.google.com/books?id=eYrl07GPkYkC&pg=RA1-PA236&dq=space+time+approach+to+quantum+electrodynamics&hl=en&ei=pACzTaMHh9-IAu-SjbAG&sa=X&oi=book_result&ct=result&resnum=1&ved=0CCkQ6AEwAA#v=onepage&q=space%20time%20approach%20to%20quantum%20electrodynamics&f=false Feynman]
Note that the {{tl|cite book}} and {{tl|cite journal}} templates used in the above coding example are formatted with the cells in a horizontal style rather than a vertical style where the cells are in a vertical column. The horizontal style looks neater and definitely uses less space. However, the horizontal style is only a suggestion, it is not mandatory.
[http://books.google.com/books?id=UzISeBGrUSYC&pg=PA916&dq=Lienard-Wiechert%2Bpotential+8&hl=en&ei=lQayTeTkK6rfiALmgoiwBg&sa=X&oi=book_result&ct=result&resnum=1&ved=0CCwQ6AEwAA#v=onepage&q&f=false Belušević]
 
[http://books.google.com/books?id=wzZQs79XJBgC&pg=PA49&dq=Lienard-Wiechert%2Bpotential+8&hl=en&ei=lQayTeTkK6rfiALmgoiwBg&sa=X&oi=book_result&ct=result&resnum=3&ved=0CDYQ6AEwAg#v=onepage&q=Lienard-Wiechert%2Bpotential%208&f=false Gould]
The information fields in the templates do not have to be filled in in any particular order (the template puts them in standard order automatically), and fields can be left blank. For readers looking for sources, the ''url'' links that the template imbeds in the titles of books and papers are helpful, and ''isbn'' or ''doi'' entries will assist readers even if the ''url'' links expire.
[http://www.amazon.com/Principles-Electrodynamics-Melvin-Schwartz/dp/0486654931/ref=sr_1_1?s=books&ie=UTF8&qid=1303512351&sr=1-1 Schwartz]
 
[http://books.google.com/books?id=dCQiejCy1kcC&pg=PP7&dq=Lienard-Wiechert%2Bpotential+8&hl=en&ei=YfaxTY7GHobliALJyJmwBg&sa=X&oi=book_result&ct=result&resnum=6&ved=0CEAQ6AEwBTgK#v=onepage&q=Lienard-Wiechert%2Bpotential%208&f=false Schwartz]
Of course, in the ''References'' section one just can type in the information ''<font color=green>xxx</font>'' in <font color=green><nowiki><ref name = MyRefName></nowiki>&ensp;''xxx''&ensp;<nowiki></ref></nowiki></font>, but an alternative is to copy and paste one of the listings below and fill it in by copying and pasting the information.
[http://books.google.com/books?id=behRnNRiueAC&pg=PA125&dq=Lienard-Wiechert%2Bpotential+8&hl=en&ei=lQayTeTkK6rfiALmgoiwBg&sa=X&oi=book_result&ct=result&resnum=5&ved=0CEAQ6AEwBA#v=onepage&q=Lienard-Wiechert%2Bpotential%208&f=false Oughstun]
{{col-begin|width=90%}}
[http://books.google.com/books?id=1dz_NoyQstUC&pg=PA88&dq=Lienard-Wiechert%2Bpotential+8&hl=en&ei=lQayTeTkK6rfiALmgoiwBg&sa=X&oi=book_result&ct=result&resnum=4&ved=0CDsQ6AEwAw#v=onepage&q&f=false Eichler]
{{col-break|width=20%}}
[http://books.google.com/books?id=LAgKcg9WexEC&pg=PA223#v=onepage&q&f=false Müller-Kirsten]
{{tl|cite book}} &emsp;
[http://books.google.com/books?id=RvZFuqw6mXEC&pg=PA426&dq=Lienard-Wiechert%2Bpotential&hl=en&ei=FNixTdbBB8TWiALFu4WwBg&sa=X&oi=book_result&ct=result&resnum=4&ved=0CDYQ6AEwAw#v=onepage&q=Lienard-Wiechert%2Bpotential&f=false Panat]
<br/><font color=green>°°°°°°°°°°°°°°°°°°°°</font>
[http://books.google.com/books?id=qw_eus7JQzEC&pg=PA230&dq=Lienard-Wiechert%2Bpotential&hl=en&ei=FNixTdbBB8TWiALFu4WwBg&sa=X&oi=book_result&ct=result&resnum=2&ved=0CCwQ6AEwAQ#v=onepage&q=Lienard-Wiechert%2Bpotential&f=false Palit]
<br/><nowiki>{{</nowiki>cite book
[http://books.google.com/books?id=r_rDg_E97MEC&pg=SL9-PA17&dq=force+magnetic+monopole+permeability+%22Coulomb%27s+law%22&hl=en&ei=p2CvTe_bGNLUiALN6c2dBA&sa=X&oi=book_result&ct=result&resnum=3&ved=0CDcQ6AEwAjgK#v=onepage&q=%20magnetic%20monopole%20&f=false Camara]
<br/><nowiki>|</nowiki> author =
[http://books.google.com/books?id=nZZu85Gq_D8C&pg=PA359&dq=Lienard-Wiechert%2Bpotential&hl=en&ei=FNixTdbBB8TWiALFu4WwBg&sa=X&oi=book_result&ct=result&resnum=5&ved=0CDwQ6AEwBA#v=onepage&q=Lienard-Wiechert%2Bpotential&f=false Smith]
<br/><nowiki>|</nowiki> editor =
[http://books.google.com/books?id=bZkaJZ5htiQC&pg=PA4&dq=Lienard+Wiechert++distributed+charge&hl=en&ei=pO6yTcScOajjiAKN_bCvBg&sa=X&oi=book_result&ct=result&resnum=3&ved=0CDkQ6AEwAg#v=onepage&q=Lienard%20Wiechert%20%20distributed%20charge&f=false classical distributed charge]
<br/><nowiki>|</nowiki> title =  
[http://books.google.com/books?id=r4cNOM1iB68C&pg=PA13&dq=action+at+a+distance+Lienard+Wiechert&hl=en&ei=1P2yTaXaHorfiALp2YiwBg&sa=X&oi=book_result&ct=result&resnum=3&ved=0CDcQ6AEwAjgK#v=onepage&q=action%20at%20a%20distance%20Lienard%20Wiechert&f=false Florian Scheck]
<br/><nowiki>|</nowiki> chapter =  
[http://books.google.com/books?id=gNsx7_9MJgEC&pg=PA184 Radiation reaction]
<br/><nowiki>|</nowiki> edition =  
[http://books.google.com/books?id=xzJLe9UOggEC&pg=PA104 Fulvio Melia]
<br/><nowiki>|</nowiki> publisher =
[http://books.google.com/books?id=xzJLe9UOggEC&pg=PA161 Radiative reaction Fulvio Melia]
<br/><nowiki>|</nowiki> year =
[http://books.google.com/books?id=gNsx7_9MJgEC&pg=PA179 Barut Radiative reaction]
<br/><nowiki>|</nowiki> pages =
[http://books.google.com/books?id=lehyOJBove0C&pg=PA33 Distributed charges: history]
<br/><nowiki>|</nowiki> url =
[http://www.amazon.com/Electromagnetic-Processes-Princeton-Astrophysics-Robert/dp/0691124442/ref=sr_1_1?s=books&ie=UTF8&qid=1303580247&sr=1-1#reader_0691124442 Lorentz-Dirac equation Gould]
<br/><nowiki>|</nowiki> isbn =
[http://www.amazon.com/Electromagnetic-Processes-Dispersive-Media-Melrose/dp/0521410258 Fourier space description]
<br/>}}
{{col-break|width=20%}}
{{tl|cite journal}}
<br/><font color=green>°°°°°°°°°°°°°°°°°°°°</font>
<br/><nowiki>{{</nowiki>cite journal
<br/><nowiki>|</nowiki> author=
<br/><nowiki>|</nowiki> title =
<br/><nowiki>|</nowiki> journal =
<br/><nowiki>|</nowiki> volume =
<br/><nowiki>|</nowiki> issue =
<br/><nowiki>|</nowiki> pages =
<br/><nowiki>|</nowiki> date =
<br/><nowiki>|</nowiki> url =
<br/><nowiki>|</nowiki> doi =
<br/>}}
{{col-break|width=20%}}
{{tl|cite web}}
<br/><font color=green>°°°°°°°°°°°°°°°°°°°°</font>
<br/>{{cite web
<br/><nowiki>|</nowiki> author =
<br/><nowiki>|</nowiki> title =
<br/><nowiki>|</nowiki> work =
<br/><nowiki>|</nowiki> publisher =
<br/><nowiki>|</nowiki> date =
<br/><nowiki>|</nowiki> url =
<br/><nowiki>|</nowiki> doi =
<br/><nowiki>|</nowiki> accessdate = 
<br/>}}
{{col-end}}
 
One fills in the fields one wants to use, and leaves the rest blank. Other fields can be found in [[CZ:Citation templates]].
 
==Notes==
{{Reflist|group=Notes|refs=
 
<ref name=template group=Notes> For details and other templates, see [[CZ:Citation templates]]</ref>
 
}}

Revision as of 07:54, 19 May 2011

See also Help:Index/Formatting/References

List-defined references (LDR) is a referencing method that moves the text of the references out of the main body of an article and into the References section at the bottom of the article.

LDR is a way to make referencing of article contents with a great deal less cluttering of the article's main body text in the edit page. Reduced clutter makes reading and revising text in the edit page much easier, and it also makes it possible to edit all the citations directly in the References section, instead of searching for them individually through the text. Creating LDR is not only cleaner than previous methods such as the <ref>-</ref> method, it is a method that will be more easily understood by new users.

Overview of how LDR works

This section explains the steps and coding to be used in the edit page of a Citizendium article in order to cite references as the sources for words or statements (sentences or paragraphs) in the main body of the article.

The user creates a short unique id (identifier or name) for each individual reference which is formatted like this:

<ref name=id/>   Note the forward slash ( / ) at the end of the id.

The id is arbitrary, but must be one word, and cannot include punctuation marks or letters like à with diacritical marks.

To cite a reference in the main body of the article, the user places <ref name=id/> for that reference immediately to the right of the statement. The same insertion may be used in multiple locations in an article however many times that reference is needed.

Then in the References section at the bottom of the article, the user lists each reference formatted like this:

<ref name=id>xxxx</ref>  Where xxxx is the reference's full description. Quotation marks enclosing the id are not needed.

Note that the forward slash ( / ) is not included after the id in the References section.

Some rules

  • Where the user wants to locate a reference for text that is followed by punctuation like a period or a comma, the insertion <ref name=id/> should be located immediately to the right of that punctuation, and should be separated from the next word or next sentence by a single blank character space.
  • In the References section, a blank line space must be provided between each listed reference.
  • Note that the list in the References section is within a template. The list must start with {{reflist|refs= and it must end with }} exactly as shown in the example coding below.

Putting it together

To summarize, the basic templates used for bibliographic information are the same {{cite book}}, {{cite journal}} and {{cite web}} templates used with the <ref>-</ref> method.[Notes 1] However, these templates are placed not in the text, but at the end of the article following a References header using {{reflist}} and the format:

{{reflist|refs=              (notice the vertical separator and refs=)
<ref name=Ref1> {{cite book ...}} </ref>  (this is first reference)
<ref name=Ref2> {{cite book ...}} </ref>  (this is second reference, separated by a space)
}}                  (these are additional final braces)

where the names "Ref1", "Ref2" are arbitrary creations of the writer. Connection to these definitions from the text is done with an insertion, such as <ref name=Ref1/>, but notice, with a forward slash.

Although not necessary to its functionality, for ease in editing, the list of named notes in the References section can be put in alphabetical order. That makes finding the note in this list easier in the event the note should be edited, for example to update a link or add to descriptive material.

Example

This is how to code the edit page of an article using "List-Defined References" :

The Sun is the dwarf star<ref name=Weissman2007p71/> at the center of the Solar System. There are eight major planets and other celestial bodies orbiting it.<ref name=Weissman2007p3/> It is extremely hot, with surface temperatures in excess of 6,000 K and a central core temperature of about 15,700,000 K.<ref name=Weissman2007p72/>

Since the Sun is about 150,000,000 kilometers away,<ref name=Weissman2007p72/> only a very small amount of its heat and light reach the Earth. By contrast, the Earth's Moon is very much smaller and very much colder.<ref name=Vasavada1999/>

==References==

{{reflist|refs=

<ref name=Vasavada1999>{{ cite journal | author=Ashwin R. Vasavadaa, David A. Paige and Stephen E. Wood | title= Near-Surface Temperatures on Mercury and the Moon and the Stability of Polar Ice Deposits | journal= Icarus | volume=141 | issue=2 |pages=pp. 179-193 | date= October 1999 |doi=10.1006/icar.1999.6175 }}</ref>

<ref name=Weissman2007p3>{{ cite book | author=Paul R Weissman |url=http://books.google.com/books?id=G7UtYkLQoYoC&pg=PA3 | title=Encyclopedia of the solar system |chapter=Chapter 1: The solar system and its place in the galaxy| edition= 2nd Edition |editor=Lucy-Ann McFadden, Paul Robert Weissman, Torrence V. Johnson, editors | publisher=Academic Press | year=2007 | pages= pp. 3 ff |isbn= 0120885891 }}</ref>

<ref name=Weissman2007p71>{{ cite book | author=Markus J Aschwanden |url=http://books.google.com/books?id=G7UtYkLQoYoC&pg=PA71 | title=Encyclopedia of the solar system |chapter=Chapter 4: The Sun | edition= 2nd Edition |editor=Lucy-Ann McFadden, Paul Robert Weissman, Torrence V. Johnson, editors | publisher=Academic Press | year=2007 | pages= pp. 71 ff | isbn= 0120885891 }}</ref>

<ref name=Weissman2007p72>{{ cite book | author=Markus J Aschwanden |url=http://books.google.com/books?id=G7UtYkLQoYoC&pg=PA72 | title=Encyclopedia of the solar system |chapter=Table 1: Basic physical properties of the sun | edition= 2nd Edition |editor=Lucy-Ann McFadden, Paul Robert Weissman, Torrence V. Johnson, editors | publisher=Academic Press | year=2007 | pages= p. 72 | isbn= 0120885891 }}</ref>

}}


This is what the above coding produces on the article page :

The Sun is the dwarf star[1] at the center of the Solar System. There are eight major planets and other celestial bodies orbiting it.[2] It is extremely hot, with surface temperatures in excess of 6,000 K and a central core temperature of about 15,700,000 K.[3]

Since the Sun is about 150,000,000 kilometers away,[3] only a very small amount of its heat and light reach the Earth. By contrast, the Earth's Moon is very much smaller and very much colder.[4]

References

  1. Markus J Aschwanden (2007). “Chapter 4: The Sun”, Lucy-Ann McFadden, Paul Robert Weissman, Torrence V. Johnson, editors: Encyclopedia of the solar system, 2nd Edition. Academic Press, pp. 71 ff. ISBN 0120885891. 
  2. Paul R Weissman (2007). “Chapter 1: The solar system and its place in the galaxy”, Lucy-Ann McFadden, Paul Robert Weissman, Torrence V. Johnson, editors: Encyclopedia of the solar system, 2nd Edition. Academic Press, pp. 3 ff. ISBN 0120885891. 
  3. 3.0 3.1 Markus J Aschwanden (2007). “Table 1: Basic physical properties of the sun”, Lucy-Ann McFadden, Paul Robert Weissman, Torrence V. Johnson, editors: Encyclopedia of the solar system, 2nd Edition. Academic Press, p. 72. ISBN 0120885891. 
  4. Ashwin R. Vasavadaa, David A. Paige and Stephen E. Wood (October 1999). "Near-Surface Temperatures on Mercury and the Moon and the Stability of Polar Ice Deposits". Icarus 141 (2): pp. 179-193. DOI:10.1006/icar.1999.6175. Research Blogging.

Additional examples can be seen in the article Set (mathematics), which is formatted using the CZ:List-defined references methodology. The article Coriolis force also is formatted using the CZ:List-defined references method, but using the template {{reflist2}}, which works in exactly the same way, but results in a two-column format for the reference listing.

A style note

Note that the {{cite book}} and {{cite journal}} templates used in the above coding example are formatted with the cells in a horizontal style rather than a vertical style where the cells are in a vertical column. The horizontal style looks neater and definitely uses less space. However, the horizontal style is only a suggestion, it is not mandatory.

The information fields in the templates do not have to be filled in in any particular order (the template puts them in standard order automatically), and fields can be left blank. For readers looking for sources, the url links that the template imbeds in the titles of books and papers are helpful, and isbn or doi entries will assist readers even if the url links expire.

Of course, in the References section one just can type in the information xxx in <ref name = MyRefName> xxx </ref>, but an alternative is to copy and paste one of the listings below and fill it in by copying and pasting the information.

{{cite book}}  
°°°°°°°°°°°°°°°°°°°°
{{cite book
| author =
| editor =
| title =
| chapter =
| edition =
| publisher =
| year =
| pages =
| url =
| isbn =
}}

{{cite journal}}
°°°°°°°°°°°°°°°°°°°°
{{cite journal
| author=
| title =
| journal =
| volume =
| issue =
| pages =
| date =
| url =
| doi =
}}

{{cite web}}
°°°°°°°°°°°°°°°°°°°°
{{cite web
| author =
| title =
| work =
| publisher =
| date =
| url =
| doi =
| accessdate =
}}

One fills in the fields one wants to use, and leaves the rest blank. Other fields can be found in CZ:Citation templates.

Notes

  1. For details and other templates, see CZ:Citation templates