Goodman,Grant k.
The Athlone Press, 1986
Buku Teks
edited by Henk Ter Heide and Frans J. Willekens
Academic Press, 1984
Buku Teks
The World Bank, [date of publication not identified]
Buku Teks
Broadbent, Kaye, author
Routledge Curzon, 2003
Buku Teks
Beasley, W.G
University of California Press , 1999
Buku Teks