On 11/29/2013 1:41 PM, Kenneth Brody wrote: [...] >> Plus only allow upto 01-31 [...] > ( ( N N & "01"-"31" ) | <0> ("1"-"9") ) [...] I leave it as an exercise to the reader as to why this would not suffice: ( ( "01"-"31" ) | <0> ("1"-"9") ) -- Kenneth Brody