http://deerchao.net/tutorials/regex/regex.htm
http://www.crifan.com/files/doc/docbook/regular_expression/release/html/regular_expression.html
http://www.regexlab.com/
http://deerchao.net/tutorials/regex/regex.htm
http://www.crifan.com/files/doc/docbook/regular_expression/release/html/regular_expression.html
http://www.regexlab.com/