Matthias Baaz Norbert Preining Richard Zach Completeness of a Hypersequent Calculus for Some First-order Godel Logics with Delta. 9 2006 conf/ismvl/2006 ISMVL http://doi.ieeecomputersociety.org/10.1109/ISMVL.2006.16 db/conf/ismvl/ismvl2006.html#BaazPZ06