to list the source(s) from which one took information, words or literary or verbal context.
to quote; to repeat, as a passage from a book, or the words of another.
to summon officially or authoritatively to appear in court.
a citation
To focus one's study upon a particular skill, field, topic, or genre.
To become distinct or separate from what is common
To make distinct or separate due to form or function.
To narrow in scope.
To be known or notorious for some specialty.
To specify: to mention specifically.
To focus one's business upon a particular item or service.