Hubert Comon Claude Marché Ralf Treinen Constraints in Computational Logics: Theory and Applications, International Summer School, CCL'99 Gif-sur-Yvette, France, September 5-8, 1999, Revised Lectures CCL Lecture Notes in Computer Science 2002 Springer 2001 3-540-41950-0 db/conf/ccl/ccl1999.html