Schiffman, Leon G., author
Prentice Hall Internasional, 2000
Buku Teks
Solomon, Michael R., author
Pearson Education, 2004
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Tisa Kumaraputri, author
Fakultas Ekonomi dan Bisnis Universitas Indonesia, 2015
UI - Skripsi (Membership)
Schiffman, Leon G., author
Prentice-Hall, 1991
Buku Teks
Schiffman, Leon G., author
Prentice-Hall, 1991
Buku Teks