Computer Science Logic 23rd International Workshop, CSL 2009, 18th Annual Conference of the EACSL, Coimbra, Portugal, September 7-11, 2009, Proceedings Grädel, Erich Heftet / 2009 / Engelsk
Proof Theory in Computer Science International Seminar, PTCS 2001 Dagstuhl Castle, Germany, October 7-12, 2001. Proceedings Kahle Reinhard Heftet / 2001 / Engelsk
