Epstein, Catherine, author
Wiley Blackwell, 2015
Buku Teks
Urton, Gary
University for Texas , 1999
Buku Teks
Mackenzie, Donald A., author
Gramercy Books, 1994
Buku Referensi
Hwang, Pae-gang, author
Jain, 2006
Buku Teks
Ainsworth, Peter B., author
Pearson Educatios, 2000
Buku Teks