Question for Admin: Posting Links To Other Sites

 Given the mention of paper modelling in the Tips and Tech column I was thinking of starting a build thread on building paper kits. I want to use readily available free downloadable kits so others who might wish to try one can do so. Some of these kits are offered from sites that also sell commercially. Is it acceptable to post links to a site that offers free paper kits? If so: even if it is a commercial site?

Scott