Lewis, N., The Compulsory Public Services of Roman Egypt, Florenz 1997, 39. Shelton, J., Ostraca from Elephantine in the Fitzwilliam Museum, ZPE 80, 1990, 221-238, hier: S. 224. Wallace, S.L., Taxation in Egypt from Augustus to Diocletian, Princeton u.a. 1937, 275-276.