Template:Book item category header/doc

Usage
Call this template on the category page of a book category subcat meant to contain peripheral items of some sort associated with the book. BOOKNAME is assumed to be the name of the book, BookCat is used to categorize the subcat, and ordinarily is assumed to be the name of the sort of things contained in the subcat. is converted to lower case in the message generated. Optional template parameter  if provided is used instead of  (and is not converted to lower case). Optional template parameter  if provided is text added just before the period at the end of the message.

For example, undefined on a category page  should produce message
 * This category contains templates used in the Transdimensional Engineering book.

on a category page  should produce
 * This category contains images used in the Transdimensional Engineering book.

and, on either page, should produce
 * This category contains fnords used in the Transdimensional Engineering book.

The message takes a slightly different form for some kinds of items, and can be adjusted in the general case. If the items are stubs; undefined on a category page  should produce
 * This category contains stubs in the Transdimensional Engineering book.

If the items are users; undefined on a category page  should produce
 * This category lists users who identify themselves as contributors to the Transdimensional Engineering book using.

In general, optional template parameter  if provided replaces the words   in the message;  on a category page   should produce message
 * This category contains appendices of the Transdimensional Engineering book.