Jones, Stephen B.
Rand McNally & Company, 1962
Buku Teks
edited by Otis W. Freeman and John W. Morris
McGraw-Hill, 1958
Buku Teks
Israel, Saul, author
Holt, Rinehart and Winston, 1980
Buku Teks
De Blij, Harm J., author
John Wiley & Sons, 2010
Buku Teks
Bradshaw, Michael, author
McGraw-Hill, 2012
Buku Teks