Pallas, D.I ... Studi Antichita Cristiana 1 544-557
Pettegrew, David K.
Pullen, Daniel J. & Tartaron, Thomas F ... 146-158
Richter, Gisela M. A.
Rife, Joseph L. & Morison, M.M ... Oxbow Books
Risser, N & Gebhard, Elizabeth R.
Robinson, Henry S.
Schwarz, Birgit