Subject headings representing individual concepts subordinate to the main topic represented by the primary heading are generally not assigned. For example, the heading Literature is assigned to a work on literature in general, and additional headings for subordinate topics such as Criticism, Fiction, Drama, Poetry, etc. are not generally assigned. Access to subordinate concepts is provided through NT (Narrower term) references.

22.2 Reference

See also:

22.0 Specific (co-extensive) entry