Codeigniter alternative to header('Location: ' . $_SERVER['HTTP_REFERER']); - Stack Overflow
Botnet Map from $_SERVER[HTTP_REFERER] - UNIX and Linux Forums
Global Variables - Superglobals Several predefined variables in PHP are "superglobals", which means that they are always accessible, regardless of scope. - ppt download
Setting the 'Referer' Header Using JavaScript - TrustedSec
Server Variables Revisited You have already encountered the predefined elements that PHP, in conjunction with your server, stores in the superglobal $_SERVER array. Generally, $_SERVER elements are made available to PHP by the server (or the shell ...
Introduction to PHP and My SQL Kirkwood Center
Web Push Php Library Example - Strict Origin When Cross Origin - Stack Overflow
Referer XSS with a Side of Link Injection
PHP referrer URL script to know how the visitor came to the page
Setting the 'Referer' Header Using JavaScript - TrustedSec