Comments: referer
2 - Yes, "referer"
This is correct. The standard HTTP header is misspelled:
http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.36
And the controller method follows that spelling:
http://api.cakephp.org/class_controller.html#e87c8e6edf53aadc511e3d050d71a494

By alex.buchanan on 12/5/08
1 - Typo
I believe that's referer(), not referrer()