1. Foundations of Databases;Abiteboul,1995
2. Complexity of some problems concerning varieties and quasi-varieties of algebras;Bergman;SIAM J. Comput.,2000
3. Playing with Boolean blocks, Part I: Post's lattice with applications to complexity theory;Böhler;ACM–SIGACT News,2003
4. Playing with Boolean blocks, Part II: Constraint satisfaction problems;Böhler;ACM–SIGACT News,2004
5. Bases for Boolean co-clones;Böhler;Inform. Process. Lett.,2005