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Penguin Books, 1973
Buku Teks
Markin, Rom J., author
John Wiley & Sons, 1982
Buku Teks
edited by Edward C. Bursk and John F. Chapman
New American Library, 1964
Buku Teks
Rachmad Widiyanto, author
Fakultas Ilmu Sosial dan Ilmu Politik Universitas Indonesia, 2005
UI - Tesis (Membership)
Lovelock, Christopher H., author
Prentice-Hall, 2005
Buku Teks