edited by Stephan Haggard, Chung H. Lee and Sylvia Maxfield
Cornell University Press, 1993
Buku Teks
World Bank, 1980
Buku Teks
edited by Richard M. Bird and Oliver Oldman
John Hopkins, 1967
Buku Teks
Curry, Steve, author
St. Martin's Press , 1993
Buku Teks
United Nations , 1987
Buku Teks