This script tests the document.referrer property. Of the five links above, only the first three will successfully load the Target page.

For some reason the 'OR' operator || does not work with referrer, or I don't know to make it work. But referrer is unusual for 2 reasons
1. It only works on web servers
2. It only works with full URLs

The work around for the script is to link multiple conditional function calls. The script is in the target page.