Unnamed

I want to write a preg_match() function to find in that multiline string :

=================================
<html>
(... cutted ...)
<h1 align="center">  
  blahhh blahh blahhh
</h1>
(... cutted ...)
</html>
=================================

I need to have in my $result[1] value : 
  
    "blahhh blahh blahhh"; 

The result can be with or without the \r and \n (if there are any) 

here is what i got yet : 

preg_match('/<h1 align="center">(.+)<\/h1>/m',$html,$result);