Leaverton, Paul E., author
Litle Brown & Co, 1978
Buku Teks
Leaverton, Paul E., author
EGC, 1987
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Muhammad Ameerul Amin Bakar, author
UMT, 2017
Artikel Jurnal
Muh. Sopiyudin Dahlan, author
Arcan, 2001
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Jogiyanto H.M., author
Andi, 1990
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