Gaya APA

S., P, D. (1998). Letters 91-120. Transl. & preface by Owen J. Blum. . Washington: Washington Catholic University of America Press.

Gaya MLA

S., Petrus, Damianus,. "Letters 91-120. Transl. & preface by Owen J. Blum. ". Washington: Washington Catholic University of America Press, 1998. Buku.