George, Richard T. de
Regents Press of Kansas, 1980
Buku Referensi
Fachru Nofrian, author
Fakultas Ilmu Pengetahuan dan Budaya Universitas Indonesia, 2004
UI - Skripsi (Membership)
Chen, Liu-Fu, author
Philosophical Library, 1948
Buku Teks
Toynbee, Arnold J., author
Oxford University Press, 1976
Buku Teks
Vos, H. de, author
G.F. Callenbach, 1966
Buku Teks