Assertion: subject heading | /r/HasProperty | subject heading system
Facets:
Source sentences:
text: For example, in the Library of Congress Subject Headings (a subject heading system that uses a controlled vocabulary), authorized terms—subject headings in this case—have to be chosen to handle choices between variant spellings of the same word (American versus British), choice among scientific and popular terms (cockroach versus Periplaneta americana), and choices between synonyms (automobile versus car), among other difficult issues.