Seymour Ginsburg and Joseph Ullian. Ambiguity in context free languages. Journal of the Association for Computing Machinery, vol. 13 (1966), pp. 62–89. - Seymour Ginsburg and Joseph Ullian. Preservation of unambiguity and inherent ambiguity in context-free languages.Journal of the Association for Computing Machinery, vol. 13 (1966), pp. 364–368. - Thomas N. Hibbard and Joseph Ullian, The independence of inherent ambiguity from complementedness among context-free languages. Journal of the Association for Computing Machinery, vol. 13 (1966), pp. 588–593.
D. Terence Langendoen · Journal of Symbolic Logic · 1968
Seymour Ginsburg and Joseph Ullian. Ambiguity in context free languages. Journal of the Association for Computing Machinery, vol. 13 (1966), pp. 62–89. - Seymour Ginsburg and Joseph Ullian. Preservation of unambiguity and inherent ambiguity in context-free languages.Journal of the Association for Computing Machinery, vol. 13 (1966), pp. 364–368. - Thomas N. Hibbard and Joseph Ullian, The independence of inherent ambiguity from complementedness among context-free languages. Journal of the Association for Computing Machinery, vol. 13 (1966), pp. 588–593. - Volume 33 Issue 2