Lieu, D.K.
Rutgers University Press, 1948
Buku Teks
Frank Cass, 1994
Buku Teks
Avramovic, Dragoslav, author
John Hopkins Press, 1972
Buku Teks
International Bank for Reconstruction and Development ; editor, Francis Adams Truslow
John Hopkins Press, 1953
Buku Teks
Coppock, Joseph D., author
McGraw-Hill Book Company, Inc., 1962
Buku Teks