Bride, Mac
Hodder Headline Plc., 1995
Buku Teks
Estabrook, Noel
Sams.net, 1997
Buku Teks
Sams Publishing, 1995
Buku Referensi
Shelly, Gary B.
Course Technology Cengage Learning, 2012
Buku Teks
Nelson, Stephen L.
Elex Media Komputindo , 1996
Buku Teks