Tatum, W Jeffrey (1999). The patrician tribune. Chapel Hill: University of North Carolina Press. pp. 117–18. ISBN978-0-8078-7206-2. LCCN98-37096. Tatum also notes that "it is not longer reasonable to conclude that all but a few collegia were made illegal".
Alexander, Michael Charles (1990). Trials in the late Roman Republic, 149 BC to 50 BC. Toronto: University of Toronto Press. Trial 220. ISBN0-8020-5787-X. OCLC41156621.