Jufrizal, author
Graha Ilmu, 2018
Buku Teks
Wilkes, Angela
Passport Books, 1987
Buku Teks
Benson, Nigel C., author
Mizan, 2000
Buku Referensi
Horrocks, Chris
Bandung : Mizan, 1997,
Buku Referensi
Hinchliffe, Alan, author
John Wiley & Sons, 2005
Buku Teks