Edited by Dagobert D. Runes
Philosophical Library, 1947
Buku Teks
Luce, J.V.
Thames and Hudson , 1994
Buku Teks
Runkle, Gerald.
Holt, Rinehart and Winston, 1985
Buku Teks
Bernard, Theos
Philosopical Library , 1947
Buku Teks
edited by John K. Ryan
The Catholic University of America Press, 1963
Buku Teks