@conference {15928, title = {A preliminary excursion into step-logics}, booktitle = {Proceedings of the ACM SIGART international symposium on Methodologies for intelligent systems -}, year = {1986}, month = {1986///}, pages = {262 - 269}, address = {Knoxville, Tennessee, United States}, doi = {10.1145/12808.12837}, url = {http://dl.acm.org/citation.cfm?id=12837}, author = {Drapkin,J. and Perlis, Don} }