A citation or bibliographic citation is a reference to a
book,
article,
web page, or other published item with sufficient detail to identify the item uniquely. Unpublished writings or speech, such as
working papers and personal communications, are also sometimes cited. Citations are provided in scholarly works,
bibliographies, and
indexes. The word citation may also mean the act of citing a work, that is, providing a reference to the work in the form of a bibliographic citation.
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