Ewing L. Lusk Ralph Butler Terry Disz Robert Olson Ross A. Overbeek Rick L. Stevens David H. D. Warren Alan Calderwood Péter Szeredi Seif Haridi Per Brand Mats Carlsson Andrzej Ciepielewski Bogumil Hausman The Aurora Or-Parallel Prolog System. 819-830 1988 FGCS db/conf/fgcs/fgcs88.html#LuskBDOOSWCSHBCCH88