title: How to access pubmed data for forms with multiple pages in python crawler
body: <p>I am trying to crawl pubmed with python and get the pubmed ID for all papers that an article was cited by.</p>
  
  <p>For example this article (ID: 11825149)
  <a href="http://www.ncbi.nlm.nih.gov/pubmed/11825149" rel="nofollow">http://www.ncbi.nlm.nih.gov/pubmed/11825149</a>
  Has a page linking to all articles that cite it:
  <a href="http://www.ncbi.nlm.nih.gov/pubmed?linkname=pubmed_pubmed_citedin&amp;from_uid=11825149" rel="nofollow">http://www.ncbi.nlm.nih.gov/pubmed?linkname=pubmed_pubmed_citedin&amp;from_uid=11825149</a>
  The problem is it has over 200 links but only shows 20 per page. The 'next page' link is not accessible by url.</p>
  
  <p>Is there a way to open the 'send to' option or view the content on the next pages with python?</p>
  
  <p>How I currently open pubmed pages:</p>
  
  <pre><code>def start(seed):
      webpage = urlopen(seed).read()
      print webpage
  
  
      citedByPage = urlopen('http://www.ncbi.nlm.nih.gov/pubmedlinkname=pubmed_pubmed_citedin&amp;from_uid=' + pageid).read()
      print citedByPage
  </code></pre>
  
  <p>From this I can extract all the cited by links on the first page, but how can I extract them from all pages? Thanks.</p>