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Buku Referensi
edited by Mari Pritchard Parker, Elvio Angeloni
McGraw-Hill, 2013
Buku Teks SO
Kelly, Robert L.,author
Wadsworth, 2010
Buku Teks SO
Kelly, Robert L.,author
Wadsworth, 2010
Buku Teks SO
edited by Susan E. Alcock, Robin Osborne
Blackwell, 2007
Buku Teks