http://stackoverflow.com/questions/18577462/how-to-make-a-tableview-divided-into-sections-by-letter-like-the-contacts-app

http://www.iphonedevcentral.com/indexed-uitableview-tutorial/

http://furnacedigital.blogspot.com/2012/02/uitableview-sections.html

http://www.cnblogs.com/MobileDevelop/archive/2010/09/26/1825020.html

http://blog.csdn.net/chyroger/article/details/5800842

http://benedictcohen.co.uk/blog/archives/230

http://www.appcoda.com/ios-programming-index-list-uitableview/