Richman, Fred, 1938-
Brooks/Cole, 1967
Buku Teks
edited by Louis G. Locke, William M. Gibson, George W. Arm
Holt Rinehart and Winston, 1966
Buku Teks
Galbraith, John Kenneth, 1908-2006
Houghton Mifflin, 1979
Buku Teks
Partlow, Robert B.
Prentice-Hall, 1963
Buku Teks
Galston, William A.
Cambridge University Press, 2005
Buku Teks SO