Ridley, B.K., author
John Wiley & Sons, 1979
Buku Teks
De Blij, Harm J., author
John Wiley & Sons, 1996
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De Blij, Harm J., author
John Wiley & Sons, 1993
Buku Teks
Briggs, David J., author
Longman Scientific & Technical, 1994
Buku Teks
Strahler, Alan H., author
John Wiley & Sons, 1997
Buku Teks