References:

1.Sir Issac Newton - English Scientist. Robin Chew. 1998. http://www.lucidcafe.com/lucidcafe/library/95dec/newton.html.

2. Newton, Issac. Eric W. Weisstein and Wolfram Research, Inc. 2000.
http://www.treasure-troves.com/bios/Newton.html

3. Newton, Sir Issac. J. A. Schuster.© 2000 Mathematics School Science Faculty, Central University of Venezuela http://euler.ciens.ucv.ve/English/mathematics/newton.html

4. WWW resources related to Issac Newton. Andrew Mcnabb. 1999. http://www.newton.org.uk/OtherWWW.html