Leonard0 - 2:48 pm on Sep 12, 2011 (gmt 0)

No, there isn't much you can do to protect your articles from persons who copy them a few at a time, as opposed to mass downloads. Some of your articles may have already been published by your subscribers.
It would probably be a good idea to copyright the articles and file DMCAs against those who infringe.
[added: see the Content, Writing and Copyright forum for more info [webmasterworld.com...]