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Buku Teks SO
Universitas Budi Luhur,
Majalah, Jurnal, Buletin
PSIKOM Univ Budi Luhur, 2015
Majalah, Jurnal, Buletin
Gamble, Teri Kwal, author
McGraw-Hill, 2005
Buku Teks
edited by Yahya R. Kamalipour
Thomson, Wadsworth, 2007
Buku Teks