Help:Cite errors/Cite error references no text

Overview
A footnote used multiple times may be defined with a name:
 * content

To invoke a named footnote:

References may also be defined within the reference list. Here is a correct example:

Use straight quotation marks " "  to enclose the reference name (size exaggerated). Do not use curly quotation marks “ ”. Curlies will simply be treated as another character, not as quotation marks. If one style of quotation marks is used when first naming the reference, but the other style is used in a reference repeat, an error message will be seen on the published page. See WP:Manual_of_Style for more information.

Issues and resolution
(This error message is sometimes mistakenly produced by the MediaWiki software, even when a named reference is correctly defined if one tries to add a webpage address (URL) in the Template:Refn without using ref tags, for example when the URL includes the equals sign =, e.g. https://www.ahdictionary.com/word/search.html?q=Ossetia.)

A named reference was invoked but never defined, or no content was provided for the definition. The reference may be defined inline or in the reference list. You may have misspelled the reference name, used special characters that look the same but are actually different, or the original named reference is missing (for example, if you just copied and pasted the invoked ref).

For instance,
 * content
 * and
 * content

are not the same: one contains a hyphen while the other uses an ndash. To avoid this sort of error, try to use only the characters available on the standard keyboard.

You may have also invoked a reference but never defined it, for example:  or.

You may have tried to include the reference inside the ref tag, for example:.

The full reference may have been removed from the article with other content, such as when removing information under BLP concerns. In this case the text of the reference will be available in the page history, and you can convert the single tag into a full reference.

List-defined references may have this error if:
 * The closing tag is missing or malformed. This would normally result in a


 * message, but the missing tag causes the reference to "eat" the reference following in the list. Since that reference is undefined, the message


 * displays for both references. This can be very confusing, as the order of references in the list may not match the order used in the content.


 * If reflist is used and the refs parameter is missing or malformed.
 * If a named reference is invoked within the reference list markup:


 * Another type of problem that will cause this error to appear relates to the location of an invoked footnote within an article. If a footnote is added to an article anywhere below reflist, then that footnote will appear at the bottom of the article. Consequently, if a footnote used in the article is invoked (like ) anywhere after reflist in an article, the cite error will appear, because reflist is only a list of all the footnotes above the reflist.

Display
If the reference name includes characters other than standard English alphabet and numerals, then those characters will be dot encoded. That is, the characters will be converted to ASCII hexadecimal and shown with a period before them. For example, a name such as  would show as. As noted at WP:NAMEDREFS: "Please consider keeping names simple and restricted to the standard English alphabet and numerals."

Standard
Here the reference named minim is invoked, but never defined:

{{pre| Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.

List-defined references
Here, the referenced named excepteur is improperly closed— it causes the reference following in the list named ipsum to not close, thus both references show an error:

{{pre| Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. Curabitur pretium tincidunt lacus.