title: Combine two b5 size pdf to single legal page
body: <p>is there any way to combine two b5 size pdf into single legal size pdf. after googling i did not find any solution. how to approach this problem. what i can use to do it. i am developing c# desktop application which will combine two b5 size pdf to single legal page. one left size and another is right side</p>
  
  <p>e.g. input</p>
  
  <pre><code>1. b5first.pdf  
  
     1234              
  
  2. b5second 
  
     567     
  </code></pre>
  
  <p>Output should be</p>
  
  <pre><code>3. legal.pdf
  
     1234 567
  </code></pre>