Cohen, Jack
The Collapse of chaos: discovering simplicity in a complex world
Penguins Books, 1994
 Buku Teks SO
Cotterill, Rodney
The Cambridge guide to the material world
Cambridge University Press, 1989
 Buku Referensi
New horizons world guide
edited by Gerald W. Whitted
Pan American World Airways, 1971
 Buku Referensi
O`Donnell, Sandra Martin
Programming for the world : a guide to internationalization
Prentice-Hall, 1994
 Buku Teks SO
Krogh, David
Biology : a guide to the natural world
Pearson, 2009
 Buku Teks