Paton, Stewart, author
Routledge, 2008
Buku Referensi
Editor: A.J. Stockwell, R. Asthon
HMSO, 1995
Buku Teks
Peng, Tan Huay, author
Marshall cavendish, 2010
Buku Teks
compiled by T. Geppert
Rupert Enderle, 1951
Buku Referensi
Li, Leyi, author
Beijing Language and Culture University, 1993
Buku Teks