Buckley, Charles Burton, author
University of Malaya Press, 1969
Buku Teks
Song, Ong Siang, author
University Malaya Press, 1967
Buku Teks
Huntington, Samuel P., author
The Belknap Press, 1981
Buku Teks
Snyder, Louis L., author
D. Van Nostrand Company, 1958
Buku Teks
Yaddani, G.
London Oxford University Press 1947
Buku Teks