citator

noun

1. An index of citations of legal cases and other sources

   “A citator will tell you the history and treatment of a case or of a statute or constitutional provision.”

2. (obsolete)One who makes a citation; a citer or citor

   “Should the perfon who is summoned conceal himself, letters are written to those among whom he is hid, signifying that he ought to surrender himself at a given time and place ; and if he has taken an asylum in a fortified castle, the citator goes either by night or by day, on foot or on horseback, cuts out three slips from a wooden rail, and places in the incision a coin and the writ of citation.”