Blatner, David
Peachpit Press, 2002
Buku Teks
Aji Kusumanto
Fakultas Ekonomi dan Bisnis Universitas Indonesia, 2009
UI - Tesis Open
McAlevey, Jane F.
Oxford University Press, 2016
eBooks
Brahmanti Prameswari
Fakultas Eknonomi dan Bisnis Universitas Indonesia, 2009
UI - Tesis Open
Cindy Arita Halim
2015
UI - Skripsi Membership