Petersen, James F., author
Brooks/Cole Cengage Learning, 2012
Buku Teks
Strahler, Arthur N., author
John Wiley & Sons, 1975
Buku Teks
Trewartha, Glenn T., author
McGraw-Hill, 1967
Buku Teks
Trewartha, Glenn T., author
McGraw-Hill, 1967
Buku Teks
De Blij, Harm J., author
John Wiley & Sons, 1993
Buku Teks