http://www.sciencejoywagon.com/physicszone
http://www.ma.utexas.edu/mpej
http://www.sciencedirect.com
http://www.mip.berkeley.edu/physics/physics.html
http://www.hazemsakeek.com/index.htm
http://www.explorescience.com/index.cfm
http://www.sacm.org/ArabicSACM/StudentServices/Universities.aspx