Laffont, Jean-Jacques, author
Harvard University Press, 1980
Buku Teks
McKenna, C.J.
Wheatsheaf book Ltd, 1986
Buku Teks
Pigou, A.C. (Arthur Cecil), 1877-1959, author
Macmillan, 1952
Buku Teks
edited by John S. Chipman, Daniel McFadden, and Marcel K. Richter
Westview Press, 1990
Buku Teks
Khan, M. Fahim,author
The Islamic Foundation , 1995
Buku Teks