Ajzen, Icek
Open University Press, 2004
Buku Teks
Ajzen, Icek
Open University Press, 2005
Buku Teks
Buku Teks
Jenkin, James
Lonely Planet Publications, 2006
Buku Referensi
edited by Daniel P. Kimble and Andrew M. Calman
Harlow Longman, 1995
Buku Teks