Rivkin, Arnold
Frederick A.Praeger Publishers, 1962
Buku Teks
Duffy, James
HArvard University Press, 1961
Buku Teks
Mazrui, Ali Al Amin
Little, Brown & Co., 1986
Buku Teks
Italiaander, Rolf
Prentice-Hall, 1961
Buku Teks
Godee-Molsbergen, E.C.
Longman, Green, 1910
Buku Teks