Greenburg, Steve, author
Alpha, 2002
Buku Referensi
Godden, Elaine
Sydney Reed Book 1988
Buku Teks
Collier, John, 1913-, author
Holt, Rinehart and Winston, 1967
Buku Teks
Knaap, Gerrit, author
KITLV Press , 1999
Buku Referensi
Emerling, Jae, author
Routledge , 2012
Buku Teks