@InProceedings{kufleitner_et_al:LIPIcs.CSL.2012.426, author = {Kufleitner, Manfred and Weil, Pascal}, title = {{The FO2 alternation hierarchy is decidable}}, booktitle = {Computer Science Logic (CSL'12) - 26th International Workshop/21st Annual Conference of the EACSL}, pages = {426--439}, series = {Leibniz International Proceedings in Informatics (LIPIcs)}, ISBN = {978-3-939897-42-2}, ISSN = {1868-8969}, year = {2012}, volume = {16}, editor = {C\'{e}gielski, Patrick and Durand, Arnaud}, publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik}, address = {Dagstuhl, Germany}, URL = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.CSL.2012.426}, URN = {urn:nbn:de:0030-drops-36888}, doi = {10.4230/LIPIcs.CSL.2012.426}, annote = {Keywords: first-order logic, regular language, automata theory, semigroup, ranker} }