Andreas Krebs, Howard Straubing. An effective characterization of the alternation hierarchy in two-variable logic. In Deepak D'Souza, Telikepalli Kavitha, Jaikumar Radhakrishnan, editors, IARCS Annual Conference on Foundations of Software Technology and Theoretical Computer Science, FSTTCS 2012, December 15-17, 2012, Hyderabad, India. Volume 18 of LIPIcs, pages 86-98, Schloss Dagstuhl - Leibniz-Zentrum fuer Informatik, 2012. [doi]
Abstract is missing.