Krystof Hoder Zurab Khasidashvili Konstantin Korovin Andrei Voronkov Preprocessing techniques for first-order clausification. 44-51 2012 FMCAD https://ieeexplore.ieee.org/document/6462554/ conf/fmcad/2012 db/conf/fmcad/fmcad2012.html#HoderKKV12