Smeins, Fred E., author
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Buku Teks
Brower, James E., author
Dubuque Wm. C. Brown , 1990
Buku Teks
Brower, James E., author
McGraw-Hill, [Boston ;1998, 1998]
Buku Teks
Eiser, Arthur L., author
Burgess , 1970
Buku Teks
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