Pelton, Joseph N., author
Mt.Airy, Maryland Lomond Books , 1974
Buku Teks
Artikel Jurnal
Tri Marlianawati, author
2006
UI - Tesis (Membership)
Watson, Tony J., author
Prentice-Hall, 2002
Buku Teks
Rustono Aji, author
Fakultas Ilmu Sosial dan Ilmu Politik Universitas Indonesia, 2003
UI - Tesis (Membership)