While assigning headings from a controlled list, such as LCSH, preferable because doing so facilitates searching, assigning uncontrolled subject headings (field 653) may be used for titles which would otherwise go without subject index terms. In the case of foreign language serials, the substantive nouns and adjectives found in the title can be translated into English and used as uncontrolled headings. Field 653 may also be useful for current terminology that has not settled down sufficiently to permit establishing the concept in a subject authority record. For further information, see CEG field 653.

See also:

15.2. Guidelines