Friedman, Milton, 1912-2006, author
Princeton University Press , 1963
Buku Teks
Weiher, Kenneth
Twayne, 1992
Buku Teks
Risjord, Norman K., author
Prentice-Hall, 1985
Buku Teks
Williams, T. Harry, author
Alfred A. Knopf, 1963
Buku Teks
Beard, Charles A., author
New Home Library, 1944
Buku Teks