Matthew Valeriote, Simone Bova, Hubie Chen. On the Expression Complexity of Equivalence and Isomorphism of Primitive Positive Formulas. In Andrei A. Bulatov, Martin Grohe, Phokion G. Kolaitis, Andrei A. Krokhin, editors, The Constraint Satisfaction Problem: Complexity and Approximability, 25.10. - 30.10.2009. Volume 09441 of Dagstuhl Seminar Proceedings, Schloss Dagstuhl - Leibniz-Zentrum für Informatik, Germany, 2009. [doi]
Abstract is missing.