Alberto Bertoni, Giancarlo Mauri, Mauro Torelli. An Algebraic Approach to Problem Solution and Problem Semantics. In Jozef Gruska, editor, Mathematical Foundations of Computer Science 1977, 6th Symposium, Tatranska Lomnica, Czechoslovakia, September 5-9, 1977, Proceedings. Volume 53 of Lecture Notes in Computer Science, pages 253-262, Springer, 1977.
Abstract is missing.