Tolong jelaskan mengenai Catatan dari Trebonianus Gallus

Bray, John. Gallienus: A Study in Reformist and Sexual Politics, Wakefield Press, 1997. ISBN 1-86254-337-2

Bowman Alan K., Garnsey Peter, Cameron Averil (ed.). The Cambridge Ancient History: The Crisis of Empire, A.D. 193–337, Cambridge University Press, 2005. ISBN 0-521-30199-8.

Potter, David S. The Roman Empire at Bay AD 180–395, Routledge, 2004. ISBN 0-415-10058-5.