Gibney, Frank
Walker and company, 1992
Buku Teks
Dupuy, R. Ernest
HAwthorn Books, 1966
Buku Teks
Brown, Stephen, author
Sage Publications, 2001
Buku Teks
Ho Kan-Chih
Peking: Foreign Language Press, 1959
Buku Teks
Jose Rizal, author
ASEAN Committee on Culture and Information, 1991
Buku Teks