Pitchford, Paul, author
North Atlantic Books, 2002
Buku Teks
Bakhru, author
Pashupati Printers, 2017
Buku Teks
Werbach, Melvyn R., author
Thorsons, 1993
Buku Referensi
Ursell, Amanda, author
A Dorling Kindersley Book, 2000
Buku Teks
Milburn, Michael P., author
The Crossing Press, 2001
Buku Teks