Bjorn Freeman-Benson and Alan Borning,  <a href="http://www.cs.washington.edu/research/projects/weird/www/kaleidoscope-iccl-92.html"> "The Design and Implementation of Kaleidoscope'90, A Constraint Imperative Programming Language"</a>, <em>Proceedings of the IEEE Computer Society 1992 International Conference on Computer Languages</em>, April 1992, pages 174-180.  <LI>
