Mylopoulos, John. Norman I. Badler, L. Melli, Nick Roussopoulos: "1.pak: A SNOBOL-based programming language for artificial intelligence applications" pp691-696

[Proceedings] (1973) Proceedings of the Third International Joint Conference on Artificial Intelligence IJCAI-73, Stanford, CA: Stanford University 1973  

Languages mentioned 1.pak {1973} Goal-directed graph-pattern-matching language