Resources+I+Used

These are the sources I used:

__Lenntech__. 28 January 2008.

Stwertka, Albert. __A Guide to the Elements.__ New York: Oxford University Press, 2002.

__Web Elements.__ 2 February 2008. 

__The Nitrogen Family__. 2 February 2008. <[|http://www.carondelet.pvt.k12.ca.us/Family/Science/Nitrogen/phosphorus.html>]

__Encyclopedia__ __Britannica Online__. 2 February 2008. 