A PHP Error was encountered

Severity: Notice

Message: Undefined index: HTTP_REFERER

Filename: controllers/Page.php

Line Number: 425

Backtrace:

File: /var/www/trial_klinik/application/controllers/Page.php
Line: 425
Function: _error_handler

File: /var/www/trial_klinik/index.php
Line: 323
Function: require_once