Howdy Wayne~
I think I can answer this one: If somebody other than you owns the copyright, it would be a violation of the law to scan the material and post it here, unless you have specific permission from the copyright owner. (BTW, the author of an article or book is typically not the copyright owner!)
Publishers are always nervous about infringing on another publisher's copyright, so we'd probably take any such material off the forum with a quickness. Much like our conservative approach to "adult" language on the forums, Kalmbach is also super-cautious about anything that might land us in court. Litigation is definitely bad for the bottom line, especially for a small company like ours.
The law does make an exception for quotations of brief passages. A whole page is too much, but if a few sentences supported a point you are making, you could quote them as long as you credit the source. (After all, academic institutions couldn't function if they couldn't do this.)
As you can imagine, digital media are having a major impact on copyright law, and the "content owners" are getting touchier about these things than they used to be. The web is full of unauthorized copies of copyrighted material, usually with no adverse consequences for the people who post it. But, technically, if copyright owners wanted to, they could sue each an every violator. In fact, I heard a news item on the radio yesterday that some of the big record companies are going to start suing selected web usesrs who download unauthorized MP3s. The statistical likelihood of being one of those unlucky people is pretty small, but talk about statistical unlikelihood with somebody who got struck by lightning. [:0]