References
. http://www.reformation.org/newton.html
(last access 22-4-2010)
. http://www.newton.ac.uk/newtlife.html
(last access 23-4-2010)
. http://www.answers.com/topic/sir-isaac-newton
(last access 22-4-2010)
. http://www.zephyrus.co.uk/isaacnewton.html
(last access 23-4-2010)