Newbigin, Marion I.
Dent & sons, Ltd., 1925
Buku Teks
Strahler, Arthur N., author
John Wiley & Sons, 1967
Buku Teks
Strahler, Arthur N., author
John Wiley & Sons, 1973
Buku Teks
Strahler, Arthur N., author
John Wiley & Sons, 1975
Buku Teks
Trewartha, Glenn T., author
McGraw-Hill, 1967
Buku Teks