PGM LVII – P. Mich in. 534 PGM LVII – P. Mich in. 534 – A cryptographic Greek ritual manual, https://quod.lib.umich.edu/a/apis/x-2437/534R.TIF Source: University of Michigan Library, Digial Collections https://quod.lib.umich.edu/a/apis/x-2437/534R.TIF
