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McGraw-Hill, 1995
Buku Referensi
Freed, Melvyn N.
Macmillan, 1991
Buku Referensi
Roberts, Albert R., editor
Gunung Mulia, 2002
Buku Teks
Kristine Krapp, Editor
Thomson Gale, 2004
Buku Referensi
Axelrod, Michael I., author
Routledge, 2017
Buku Teks