edited by, Frank Gaynor
Philosophical Library, 1953
Buku Referensi
Collins, John Edward, author
Rowman & Littlefield, 1991
Buku Teks
Nicholson, Reynold Alleyne, author
University Press , 1967
Buku Teks
Al-Attas, Syed Muhammad Naguib
Kuala Lumpur : University of Malay Press, 1970.
Buku Teks
Suzuki, Daisetz Teitaro, 1870-1966, author
Harper, 1957
Buku Teks SO