Johannes Köbler, Uwe Schöning, Jacobo Torán. On Counting and Approximation. In Max Dauchet, Maurice Nivat, editors, CAAP 88, 13th Colloquium on Trees in Algebra and Programming, Nancy, France, March 21-24, 1988, Proceedings. Volume 299 of Lecture Notes in Computer Science, pages 40-51, Springer, 1988.
Abstract is missing.