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McGraw-Hill , 1964
Buku Teks
edited by Clifton R. Wharton
Aldine Publishig, 1969
Buku Teks
Food and Agriculture Organization of the United Nations , 1985
Buku Teks
Bhaduri, Amit
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Buku Teks
Schultz, Theodore W.
The Minchigan of Univ. Press, 1966
Buku Teks