Pustaka Sinar Harapan; Media Interaksi Utama, 1996
Buku Referensi
Black Book Marketing Group
Black Book Marketing Group, 1995
Buku Teks
Grolier, 1995
Buku Referensi
editor, A.E. Pegg
Portland Press, 1995
Buku Referensi
Miller, Johnm, author
Kogan Page, 1994
Buku Referensi