Peter Salim
Modern English Press, 1993
Buku Referensi
Pass, Chirtopher
Erlangga, 1997
Buku Referensi
Collin, P. H.
Peter Collin Publishing, 2001
Buku Teks
Kurian, George Thomas
Amacom, 2013
Buku Referensi
Oxford reference
Oxford University Press, 1990
Buku Referensi