Use of license in ports Makefile

[Carmel]

I have a application that I want to port to FreeBSD. It is licensed
under the BSD license from what I can understand. In the new port's
Makefile, would I just put something like this:

license:	BSD

or would that not work? Suppose it was licensed under a "public domain"
license. How would that be handled or isn't it important in that case.

Finally, do I have to use anything other than:

.include <bsd.port.mk>

in the Makefile? I cannot seem to locate a lot of this information in
the porter's handbook; although I thought I should have.

Thanks!

-- 
Carmel 
carmel_ny at hotmail.com