http://tutsforweb.blogspot.com/2012/05/user-registration-with-codeigniter.html

User Registration with Codeigniter

http://stackoverflow.com/questions/14508339/codeigniter-email-verification-pass-parameters

Codeigniter email verification pass parameters

http://learnwithgireesh.blogspot.com/2012/06/email-verification-

Email Verification using codeigniter

using-codeigniter.html