Rollason, Russell G., author
Alternative Pub. Cooperative, 1981
Buku Teks
Williamson, John
Basic Books, Inc., 1983
Buku Teks
Isaak, Robert A.
Prentice-Hall, 1991
Buku Teks
Bedjaoui, Mohammed, author
Gunung Agung, 1983
Buku Teks
Lewis, William Arthur, 1915-, author
Princeton University Press, 1978
Buku Teks