It is necessary to seek corroboration or verification of the term in other sources. Any individual work may or may not be accurate, may or may not be authoritative, or may or may not present or advocate a particular point of view. Although the concept may be found only in the work being cataloged, other sources appropriate to the subject area in question should be cited to demonstrate that the concept was properly investigated. There will be some situations, for example, with archeological sites or computer languages, where the only information may be in the work being cataloged. In those cases, it is helpful to cite definitions or explanatory information in the work.
Preference is given to reference sources like dictionaries, encyclopedias, indexes, and thesauri.
Checking for usage in titles is a good means of finding variant terminology for UF references. Appropriate sources should be checked for special topics, like MeSH and Dorland's medical dictionary for medical terms, AAT for art, NASA Thesaurus for astronautics, chemistry dictionaries for chemicals, etc. How much authority work is sufficient will vary with the topic and what is found in reference sources. It is sometimes necessary to weigh the information found in various sources and to determine which source is more authoritative or current. If the information in the work cataloged is confirmed in an authoritative source, that is probably all that is needed.