Hoffman, Frederick J.
The Free Press, 1962
Buku Teks
McConnell, Grant
Alfred A. Knopf, 1967
Buku Teks
Lake, Anthony
Little, Brown and Company, 2000
Buku Teks
Galbraith, John Kenneth, 1908-2006
Houghton Miffiln, 1952
Buku Teks
Dolbeare, Kenneth M.
D.C. Heath, 1985
Buku Teks