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Chicago Dryden Press, 1990
Buku Teks
Schiffman, Leon G., author
Pearson, 2015
Buku Teks
Schiffman, Leon G., author
Prentice-Hall, 1997
Buku Teks
Schiffman, Leon G., author
Pearson Education, Inc., 2007
Buku Teks
Schiffman, Leon G., author
Pearson Education International, 2004
Buku Teks