PHP include problems

Hello,

I am trying an alternative for the Iframes, by trying to use php includes.
I have tried several plugins but cant seem to get it working.
To be more exact, I tried:
exec php
add post url
include me
and MaGiKS Proper PHP Include

I need to include several sites with an form on it, just like this one:
http://proef-abonnementen.nu.site-id.nl/servlet/___?action=href&cid=982&sid=4669&pid=3

I have tried <?php include(“http://proef-abonnementen.nu.site-id.nl/servlet/___?action=href&cid=982&sid=4669&pid=3&#8221;); ?>
and some more, which at the moment I cannot find back. But I keep getting nothing or an error message.

I am not a wizzard with php, and never worked with the include tags before. Could someone help me out please?