If a single, general heading covering all topics treated in a work on four or more topics is available or can be established, it is assigned even if it includes other topics not covered in the work being cataloged. An exception is made for a work on just four topics if the general heading is very broad and each topic covered in the work forms only a small portion of the subject represented by the general heading. In this case, each of the four topics is given a specific heading. Examples

26.62 Reference

See also:

26.6 Works on multiple topics