Strahler, Arthur N.
Introduction to physical geography
John Wiley & Sons, 1973
 Buku Teks SO
Strahler, Arthur N.
Introduction to physical geography
John Wiley & Sons, 1967
 Buku Teks SO
Strahler, Arthur N.
Physical geography
John Wiley & Sons, 1975
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Duckson, Don W.
Exercise in physical geography
McGraw-HIll, 1999
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Blij, Harm J.. de
Physical geography of the global environment
John Wiley & Sons, 1996
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