Grubel, Herbert G., author
Lexington Books, 1973
Buku Teks
edited by Johannes Dragsbaek Schmidt, Jacques Hersh; Niels Fold
Longman, , 1997
Buku Teks
edited by Saw Swee-Hock
Institute of South East Asia Studies, 2011
eBooks
Fifield, Russell H., author
Harper, 1958
Buku Teks
Center for Strategi and International Studies, 1975
Buku Teks