Millikan, Max F., author
Little, Brown , 1967
Buku Teks
Mellor, John W., author
Cornell University Press, 1966
Buku Teks
Clayton, Eric, author
Macmillan, 1983
Buku Teks
Report of a SEADAG Rural Development Seminar Meeting, 1969
Buku Teks
Berry, R. Albert, author
Md. Johns Hopkins University Press , 1979
Buku Teks