Sampson, Roy J.
Houghton Miffiln, 1971
Buku Teks
Prianso, author
Fakultas Ilmu Pengetahuan dan Budaya Universitas Indonesia, 2003
UI - Skripsi (Membership)
White, James J., author
West Group, 1995
Buku Teks
Davis, Joel, 1950-, author
Prentice-Hall, 1997
Buku Teks
Modelski, George, author
Frederick A. Praeger, 1962
Buku Teks