15th Annual Symposium on Switching and Automata Theory (swat 1974) (1974)
Oct. 14, 1974 to Oct. 16, 1974
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/SWAT.1974.8
Two characterization theorems for the class of context-free grammatical families are given. The characterizations are expressed in terms of the family of regular sets, the family of linear sets, and the following language-family operators: union, concatenation, the full semi-AFL operator, the full AFL operator, and a new ternary substitution operator.
A. Cremers and S. Ginsburg, "Characterization of context-free grammatical families," 15th Annual Symposium on Switching and Automata Theory (swat 1974)(FOCS), vol. 00, no. , pp. 199-204, 1974.