This is a tracking category. It is used to build and maintain lists of pages—primarily for the sake of the lists themselves and their use in article and category maintenance. It is not part of the encyclopedia's categorization scheme. More information: This category is hidden on its member pages—unless the corresponding user preference is set. These categories are used to track, build and organize lists of pages needing "attention en masse" (for example, pages using deprecated syntax), or that may need to be edited at someone's earliest convenience. These categories also serve to aggregate members of several lists or sub-categories into a larger, more efficient list (discriminated by classifications).

Administrators: Please do not delete this category even if it is empty! This category may be empty occasionally or even most of the time.

This is a hidden tracking category for CS1 citations that use |author=, or its aliases.

Articles are listed in this category when Module:Citation/CS1 identifies cs1|2 citation templates that appear to use singular forms of author name-list parameters to list multiple authors' names. Doing so corrupts the citation's metadata.

The citation module code looks for multiple comma or semicolon separator characters in the value assigned to |author=, |last=, their aliases, and enumerated equivalents (e.g. |author2=, |last2=, etc.). This test displays an error message for multiple authors' names in a single parameter, as well as single author names that include a comma-separated list of post-nominals: |author=FC White, RN, MD, Ph.D.

To fix these errors in citations:

1. Remove post-nominals.
2. Provide enumerated author parameters (e.g. either |author2= or |last2= and |first2=) for each author of a cited work.
3. When multiple separator characters are legitimately present in a name (commonly a corporate, institutional, or governmental author), the name may be wrapped in <nowiki>...</nowiki> tags to suppress assignment to this category, like this: |author=<nowiki>Federal Ministry of Transport, Building, and Urban Development</nowiki>.

Editors should not simply replace |author= with |authors=. Using the plural |authors= parameter to replace a singular |author= or |last= parameter that holds multiple authors' names is discouraged because automatically decoding lists of human names is an extraordinarily difficult task. Because of this difficulty, names listed in |authors= are omitted from the template's COinS metadata. Enumerating the author list with |authorn=, or |lastn= / |firstn=, or, where appropriate, |vauthors=, preserves the associated metadata.

Pages in this category should only be added by Module:Citation/CS1.

By default, Citation Style 1 and Citation Style 2 error messages are visible to all readers and maintenance category messages are hidden from all readers.

To display maintenance messages, include the following text in your common CSS page or your specific skin's CSS page (common.css and skin.css respectively):

.mw-parser-output span.cs1-maint {display: inline;} /* display Citation Style 1 maintenance messages */

To display hidden-by-default error messages:

.mw-parser-output span.cs1-hidden-error {display: inline;} /* display hidden Citation Style 1 error messages */

Even with this CSS installed, older pages in Wikipedia's cache may not have been updated to show these error messages even though the page is listed in one of the tracking categories. A null edit will resolve that issue.

To hide normally-displayed error messages:

.mw-parser-output span.cs1-visible-error {display: none;} /* hide Citation Style 1 error messages */

You can personalize the display of these messages (such as changing the color), but you will need to ask someone who knows CSS or at WP:Simple talk if you do not understand how.