Wolfgang Ahrendt Bernhard Beckert Reiner Hähnle Peter H. Schmitt KeY: A Formal Method for Object-Oriented Systems. 32-43 2007 conf/fmoods/2007 FMOODS http://dx.doi.org/10.1007/978-3-540-72952-5_2 db/conf/fmoods/fmoods2007.html#AhrendtBHS07