http://en.wikipedia.org/wiki/Lewis_structure
http://www2.chemistry.msu.edu/faculty/reusch/virttxtjml/Images/lewstrc1.gif
http://www.sciencedaily.com/articles/l/lewis_structure.htm
http://chemistry.about.com/od/workedchemistryproblems/a/How-To-Draw-A-Lewis-Structure-Octet-Exception.htm
http://fa.wikipedia.org/wiki/%D8%B3%D8%A7%D8%AE%D8%AA%D8%A7%D8%B1_%D9%84%D9%88%D9%88%DB%8C%D8%B3
http://www.kanoon.ir/Article/23072/%DA%86%D9%86%D8%AF_%D9%86%DA%A9%D8%AA%D9%87_%D8%AF%D8%B1_%D8%B1%D8%A7%D8%A8%D8%B7%D9%87_%D8%A8%D8%A7_%D8%B3%D8%A7%D8%AE%D8%AA%D8%A7%D8%B1_%D9%84%D9%88%D9%88%D9%8A%D8%B3%D8%B4%D9%8A%D9%85%D9%8A2.htm
http://catalyst.parsiblog.com/Posts/88/%D8%B1%D8%B3%D9%85+%D8%B3%D8%A7%D8%AE%D8%AA%D8%A7%D8%B1+%D9%84%D9%88%D9%88%D9%8A%D8%B3+%D9%85%D9%88%D9%84%DA%A9%D9%88%D9%84+%D9%87%D8%A7/
http://shimikonkoor.blogfa.com/post/52
http://amozeshshimi.persianblog.ir/post/56/
http://shimi2-3.lxb.ir/post/71
http://en.wikipedia.org/wiki/Resonance_(chemistry)
http://www.merriam-webster.com/dictionary/resonance%20hybrid
http://www.shimiozendegi.blogfa.com/8912.aspx
http://chemistry.about.com/od/famouschemists/p/lewisbio.htm
http://chemistry.about.com/od/generalchemistry/a/lewisstructures.htm
