The <dotj:referer> tag determines where the user came from prior to visiting this page. There are two ways
to use this tag:
The first way is to simply display the referer in your page. To do this, omit the "id" attribute
and the referer string will replace the tag. For example,
You came from the following URL:
The second way is to supply the "id" attribute. In doing this, the
referer will not display, but you can retrieve the referer programmatically.