Maritain, Jacques
Philosophical Library, 1951
Buku Teks
Koren, Henry J.
Duquesne University, 1960
Buku Teks
Chu, Hsi, author
Probsthain, 1922
Buku Teks
Kelsen, Hans, author
Kegan Paul : Trench : Trubner , 1946
Buku Teks
edited by Scott Walden
Blackwell, 2007
Buku Teks