Lawyer, often, in court briefs

• Police officer, when ticketing
• Term paper author, for one
• One making references
• Police officer, when writing a ticket
• Policeman, at times
• Person quoting
• Footnote writer

Wiktionary Word definitions in Wiktionary
n. One who cites.

Wikipedia Word definitions in Wikipedia
Citer may refer to: CITER 155mm L33 Gun , artillery gun used by the Argentine Army Citer , French car rental company Citers , French village and commune