Amrose, James
John Wiley & Sons, 2000
Buku Teks SO
Amrose, James
John Wiley & Sons, 2000
Buku Teks SO
Parker, Harry
John Wiley & Sons, 1984
Buku Teks SO
Parker, Harry S.
John Wiley & Sons, 1991
Buku Teks SO
prepared by the Special Publications Division, National Geographic Society, Washington, D.C.
The National Geogarphic Society, 1986
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