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Buku Teks
Adam Ritcjie, Randall Thomas, editor
Taylor & Francis Group, 2009
Buku Teks
McDermott, Constance, author
Earthscan, 2010
Buku Teks
Cunningham, William P., author
McGraw-Hill, Higher Education, 2009
Buku Teks
Cunningham, William P., author
McGraw-Hill, 2002
Buku Teks