Evans, Ellis D.
Holt, Rinehart and Wiston, 1971
Buku Teks
Nicola Yelland
Open University Press, 2010
Buku Teks
Hofstede, Geert, author
McGraw-Hill, 2005
Buku Teks
edited by John C. Condon and Mitsuko Saito
Simul Press, 1978
Buku Teks
Fathia Adani Harsya, author
2018
UI - Skripsi (Membership)