White, Jon, author
Business Book Limited, 1991
Buku Referensi
Morley, Michael, author
Palgrave, 2002
Buku Teks
Stone, Norman
McGraw-Hill, 1991
Buku Teks
Ressi Putri Avicenia, author
[Fakultas Ilmu Sosial dan Ilmu Politik Universitas Indonesia, ], 2014
UI - Makalah dan Kertas Kerja
Rashelle S. Karp, editor
[American Library association, American Library association], 2002
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