Springer violates copyright!

"As most of you know, Charles Wells and I published Toposes, Triples, and Theories in 1984. Several years later, the book was sold out and, in accordance, I believe, with the 1980 copyright law, they had to reprint or return the copyright to the authors. They chose the latter option. They sent us letters saying that we were now the owners of the copyright. Unfortunately, neither of us has saved the letter. Nonetheless they did return the copyright. Browsing their web site a couple months ago, I noticed that they are selling the book again, just as though they still own the copyright. They are selling an electronic version, as well as what they describe as a paperback version, which is almost surely print-on-demand. I haven't looked (I would have to pay to) but I assume that what they are selling is a scan of the inferior printed version. (It is inferior owing to the use of a poor quality printer.) Needless to say that have not offered either of us any royalties. They have also ignored a complaint I wrote them. Most of you probably know that a slightly revised and corrected version is available free as TAC reprint #12 as well as on both Charles's and my web sites. And any copy shop will print and bind you a copy more cheaply than Springer."