Wikipedia:Advanced footnote formatting

The topic of advanced footnote formatting[essay] involves techniques for coding remote footnotes of pronunciations or examples, plus indentation and line-splitting. Many articles could use remote footnotes, such as explaining various ways some words are pronounced:
 * The term "time dilation"[p] refers to a slowing of elapsed duration.
 * Notes  [p] – The word dilation is pronounced "dy-LAY-shun" and is the preferred term.

The superscript "[p]" can be coded by just the short wikilink: [p]. The full, detailed content of that footnote text is not in the upper text of the article but, instead, is coded within the section named "Notes" (or "References"). See below: Remote footnotes & Footnotes within footnotes.

Also, indentation and line-splitting can be used, such as for long URL webpage names, when coding footnotes in an article. For example: In the above example, each part of the ref-tag footnote is indented (3 spaces) from the left margin. Due to a Wikipedia quirk, the first footnote on a page cannot be indented, because it is treated as a quotebox.

There are numerous styles for displaying footnotes (or endnotes) in a Wikipedia article. There are also many predefined footnote templates (see WP:Citation templates), but with limitations, so (as of March 2012), footnotes also can be hand-formatted to best fit each article.

Remote footnotes
Many terms could use a remote footnote, not cluttering the upper text of page, such as for explaining pronunciations or showing some detailed examples: [p] – Dilation is pronounced "dy-LAY-shun".
 * The term "time dilation"[p] refers to a slowing of elapsed duration.
 * Notes

Note that in the pronunciation footnote [p], the word "time" is considered obvious, and the syllables for "dy-LAY-shun" are shown with capital letters for emphasis, but there is also ample space to show the IPA-format within the same footnote as well.

The footnote's superscript "[p]" can be coded by just a short wikilink: [p]. The full, detailed content of that footnote text is not at the top of the article but, instead, is coded within the section named "Notes", thus shifting all that text into the Notes section, and deferring details away from the main text of an article. The Notes section could be coded as:

Since the actual footnote text (of a remote footnote) is written at the bottom of an article page, there is ample space to also compare formal versus local pronunciations of town names, without cluttering an article's top text.

Notice how several footnotes can all be linked to the section title "Notes" because that link goes to the entire Notes section. Each remote footnote can link "Notes" as in: [a] or [b]  or [example] , displaying:  [a] [b]  [example]. The full coding of the 3 superscripts could be as:
 * [a] [b] [example]

All 3 superscripts "[x]" are combined within the tags "&lt;sup>" & "&lt;/sup>". Perhaps 20 remote footnotes could be coded in a similar manner, all linked to the section title named "Notes". For logical placement, the remote footnotes should be defined above the "&lt;references/>" tag (or {&#123;Reflist}} ) which displays the other, numbered ref-tag footnotes.

Although there are other methods to link named-footnotes, the use of the remote footnotes is a very simple method to allow dozens of special footnotes, without depending on complex wiki-features which might change next week. In this case, the term "advanced footnotes" also means: sophisticated enough to still work when Wikipedia is changed (as typically happens every few months). Also, the coding of remote footnotes is likely to work on any other-language wikipedia or on any wiki website, as well.

Footnotes within footnotes
Remote footnotes can contain other remote footnotes, or include ref-tag footnotes. Also, any ref-tag footnote ("&lt;ref>...&lt;/ref>") can contain a remote-footnote link, circumventing the 15-year problem where a ref-tag footnote cannot contain another ref-tag footnote.

An example (of footnotes within footnotes) would be:
 * The term "time dilation"[p] refers to a slowing of elapsed duration.
 * Notes  [p] – The word dilation is pronounced "dy-LAY-shun" [a] and is the preferred term.[b]   [a] – Merriam-Webster Dictionary lists "dilation" with pronunciation: \dī-'lā-shən\.[ c]   [b] – The term "time dilation" has been used since 1934 but is sometimes called "time dilatation".[ d]   [c] – Merriam-Webster Online Dictionary, 2009, webpage: MW-dilation.   [d] – Merriam-Webster Online Dict., 2009, webpage: MW-time+dilation.

Nested footnotes can be used to address several common issues that would tend to clutter the top-text of an article:
 * Dates differ: some sources give one date while others give another date, and a remote footnote could explain the reasons.
 * The fact is not so simple: September 11th is often the 12th in some specific later time zone, and could be noted.
 * Opinions differ: perhaps explain how the Hatfields and McCoys stated different views of events.
 * A pronunciation differs with local residents or slang, such as NOLA spoken as "Nawlins" or "New Orluns" or "New Orleens" (etc.), so a footnote could list them, plus link further footnote sources for each.

There is no limit to the nesting of remote footnotes within other footnotes.

Indenting and line-splitting
A very long footnote can be indented and line-split, as in the following example that uses Template:Cite_book, showing a long URL for a webpage from Google Books:

Note the above line-splitting of the 6-line URL (for the webpage in Google Books) uses the HTML comment tokens "&lt;!--" and "-->". Each part of the footnote coding is placed on a separate line, thereby allowing each part to be indented from the lefthand side. There must be no spaces added to the URL (which is a single string of characters where spaces are coded "%20"). Do not add spaces before "&lt;!--" or after "-->" within the URL. However, when splitting an italicized phrase or long wikilink (" xx xx xx "), consider putting a space after "-->" on the 2nd line.

Similar indentation has been used for many decades, as in coding for computer programming, to visually separate sections of text. The indented lines typically reflect a lower-level of details (or lower-level of "abstraction" ) than the level of the outer lines. Indenting the footnote coding can help clarify sections of text that contain several footnotes, as is typical in large articles.

For over 14 years, Wikipedia has used similar line-splitting of infobox coding, putting infobox template parameters on separate lines. Decades of usage has shown that leading vertical-bars ("|") are less error-prone than trailing vertical-bars placed at the end of a line. Because leading bars can be aligned down a column, they are more easily proofread than ending bars, which tend to zig-zag along a ragged right margin.

Line splitting first footnote of page
Because of a Wikipedia formatting quirk, the first footnote on a page might be treated as a quotebox when indented (as during May 2009). However, the indentation can be simulated, by line-splitting with HTML comments, between all lines within &lt;ref>....&lt;/ref>:

The above line-splitting of the entire footnote text, into 4 lines, allows it to be coded as the first footnote of a page. Note that the first footnote might be in an infobox, appearing at the top of a page.

Page numbers
Although the issue of citing page numbers might not seem very advanced, many Wikipedia footnotes to books or journals have omitted the page numbers. Without specific page numbers, the verification of text can be extremely tedious for large books or magazines, like finding a needle in a haystack. In the wp:CS1 cite templates, there is often confusion between the parameters "page=15" and "pages=750":
 * or      – the specific page(s) in the book/journal/etc.
 * – show "page 15" in the footnote.
 * – as page 34 of 750 total pages
 * – show "end of p. 87" as page number

The exact usage of parameters can vary from template to template. Some URLs reveal a page-number parameter (such as "pg"). For example, in weblinks to Google Books, the parameter "pg=PA569" indicates "page 569" will be linked from that book.

Deferring details
Another major technique for clarifying text, containing many footnotes, is to defer the footnote details to later parts of the article, such as using named ref-tags and putting "see: External links" for URLs. For example, listing 3 footnotes: In the above example, the 3 footnotes are reduced to just short ref-name tags at first, then later expanded to show more details. However, they defer the extreme details for publisher, ISBN, and webpage-URL links to be contained as entries under "External links". Using that advanced method, no publisher names, ISBN numbers or long URL names appear in the upper article text for those 3 footnotes.

Each full footnote is coded within 3 lines of text, even though indented and pinpointing the page numbers. The tedious details are all deferred into the section "External links" (or else "References") at the bottom of the article. That separation is possible by repeating the author name and title in each entry when listed in the bottom sections. So, full footnotes can become a 3-line indentation, rather than the typical 6 or 9-line blobs that clutter many articles.

List website and beware wp:BLACKLIST sites
May 2018: A cite should show the website for an online source, such as with cite parameters "website=" or "via=" in the wp:CS1 cite templates. In accordance with Wikipedia policy "WP:LINKVIO", an article should not have links to websites that post content violating any copyrights, such as a webpage which lists song lyrics without proper notice. For banned spam websites, wp:BLACKLIST explains other restrictions, with specific problem websites coded on webpage MediaWiki:Spam-blacklist, which lists over 7,000 banned sites.

Recap of multi-level footnotes
As explained above, footnotes can be structured as either indented text, or remote footnotes (with contents under "Notes"), or simple deferred references (such as "&lt;ref name=MD/>"). There is no longer any logical reason to have article text cluttered with large blobs of footnotes that clog sentences. Beyond the clarified structure, the use of remote footnotes also allows "footnotes within footnotes" (above) to, step by step, explain detailed reasoning within footnotes that can defer to still other footnotes for sub-reasons, or for further sources about each point presented.

Advancement shock
Even though the basic ideas of advanced footnote-formatting are simple, there are many people who will fight against indenting the footnote coding (yet readily accept infoboxes with indented parameters coded down the page). There are also other people who might insist that the first footnote reference be a typical 9-line blob with full URL details, cluttering the text. They will reject a top footnote such as "&lt;ref name=MD/>" which defers details to be defined in a subsequent use of the same-named footnote.

It might be possible to get those people to read and study this essay, but if not, don't try to fight people with severe mindsets. Just move on to one of the other thousands of Wikipedia articles that need footnote clarification.