Caligula and Germanicus, Gortyna, Crete AE20, 

GAION KAISARA GERMANIKON SEBASTON, Bare head of Caligula right.
GERMANIKON KAISARA ERI AYGOYREINW GORTY, bare head of Germanicus right. 

RPC 1022; BMC 81; Vagi 523var. 

Courtesy of Helios Auction 5, June 2011