title: Passing inbound query string to outbound links
body: <p>Inbound visitors are arriving at our website with a query string that serve as credentials.  (e.g.oursite.com/landingpage.php?id=abc&amp;token=def)</p>
  
  <p>After visiting pages in any order, they arrive at a final page with an outbound link that we wish to have the same query string appended to.
  (e.g. a href="nextsite.com/targetpage.php?id=abc&amp;token=def" ...)</p>
  
  <p>What is the most effective way to keep track of the query string name value pairs as they visit other pages in order to reconstruct it on the outbound links?  (The attribute names of the name-value pairs will remain unchanged for all users.)  Is it to put them into session data?  Code examples for how to save and how to retrieve would be appreciated.</p>