http://www.glencoe.com/sites/common_assets/workbooks/science/PhysicsPPIN/pppcr1-5se.pdf
http://www.coiradio.com/library/library/ethics/the_codes_of_training/index.htm
http://www.furryelephant.com/player.php?subject=physics&jumpTo=ee/3Ms28-

http://academic.reed.edu/chemistry/roco/Potential/electrostatic_potential.html

biology notes

http://www.ibguides.com/biology/notes/nerves-and-hormones