Related sites:

• regular-expressions.info

  Regular-Expressions.info - Regex Tutorial, Examples and Reference - Regexp Patterns

• regexlib.com

  Regular Expression Library

  

• regexbuddy.com

  RegexBuddy: Learn, Create, Understand, Test, Use and Save Regular Expression

  

• regextester.com

  Regex Tester and Debugger Online - Javascript, PCRE, PHP

  

• txt2re.com

  txt2re: headache relief for programmers :: regular expression generator

  

• pcre.org

  PCRE - Perl Compatible Regular Expressions

  

• regexlab.com

  Regular Expression Laboratory - Makes regex more easy and efficient