Tsutomu Kamimura, Giora Slutzki. DAGs and Chomsky Hierarchy (Extended Abstract). In Hermann A. Maurer, editor, Automata, Languages and Programming, 6th Colloquium, Graz, Austria, July 16-20, 1979, Proceedings. Volume 71 of Lecture Notes in Computer Science, pages 331-337, Springer, 1979.
Abstract is missing.