Strahler, Alan A., author
John Wiley & Sons, 1996
Buku Teks
Moore, W. G., author
Penguin Books, 1974
Buku Referensi
Moore, W. G.
Penguin, 1974
Buku Referensi
Strahler, Arthur N., author
John Wiley & Sons, 1973
Buku Teks
Mather, P.M., author
John Wiley & Sons, 1976
Buku Teks