help writing http referrer to cookie

Hey...I'm trying to create a cookie on the user's machine that includes the referral url. I then plan to call the data from the cookie in a script that is called on my thank you page to track sales.

Why won't the following script work? It's writing "$_SERVER["HTTP_REFERER"]" to the cookie instead of the referrer URL.

<?php
$value = '.$_SERVER["HTTP_REFERER"].';
setcookie("solvotrack", $value, time()+2592000);  /* expire in 30 days */
?> 

Code (markup):

Thanks!

 

Take out the dots and quotes.

$value = $_SERVER['HTTP_REFERER'];