Collin, P. H.
Peter Collin Publishing, 2001
Buku Teks
Greener, Michael
Penguin books, 1994
Buku Referensi
Peter Salim
Modern English Press, 1993
Buku Referensi
Pass, Chirtopher
Erlangga, 1997
Buku Referensi
Kurian, George Thomas
Amacom, 2013
Buku Referensi