9th Annual Symposium on Switching and Automata Theory (swat 1968) (1968)
Oct. 15, 1968 to Oct. 18, 1968
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/SWAT.1968.7
A derivation in a phrase-structure grammar is said to be k-bounded if each word in the derivation contains at most k occurrences of nonterminals. A set L is said to be derivation bounded if there exists a phrase-structure grammar G and a positive integer k such that L is the set of words in the language generated by G which have some k-bounded derivation. The main result is that every derivation-bounded set is a contextfree language. Various characterizations of the derivation-bounded languages are then given. For example, the derivation-bounded languages coincide with the standard matching-choice sets discussed by Yntema. They also coincide with the smallest family of sets containing the linear context-free languages and closed under arbitrary substitution.
S. Ginsburg and E. H. Spanier, "Derivation-bounded languages," 9th Annual Symposium on Switching and Automata Theory (swat 1968)(FOCS), vol. 00, no. , pp. 306-314, 1968.