title: Setting paper size in FPDF
body: <p>i want to seting paper size in fpdf to a half of letter size, it's approximately 8.5x5.5 inc.    How can i do that?<br>
  My fpdf function in php language is        </p>
  
  <pre><code>$pdf = new FPDF('P','mm','?????');
  </code></pre>
  
  <p>is there any solution? Thank's before for your help..</p>