Lilia Georgieva Ullrich Hustadt Renate A. Schmidt Hyperresolution for guarded formulae. 163-192 2003 36 J. Symb. Comput. 1-2 http://dx.doi.org/10.1016/S0747-7171(03)00034-8 db/journals/jsc/jsc36.html#GeorgievaHS03