Risjord, Norman K.
Prentice-Hall, 1985
Buku Teks
Williams, T. Harry
Alfred A. Knopf, 1963
Buku Teks
Beard, Charles A.
New Home Library, 1944
Buku Teks
Alden, John Richard
American Book Company, 1960
Buku Teks
edited by Frank Freidel and Norman Pollack
Rand McNally, 1963
Buku Teks