Some classifications of context-free languages

On the computational complexity of algorithms

Juris Hartmanis, Richard E. Stearns · Transactions of the American Mathematical Society · 1965 · 957 citations · Full text

Computing, Computer Science, Mathematics +15

Revised report on the algorithmic language ALGOL 60

John Backus, Friedrich L. Bauer, J. Green et al. · Communications of the ACM · 1963 · 909 citations · Full text

Computing, Computer Science, Mathematics +3

The mathematical theory of context-free languages

H. P. Edmundson · Information Storage and Retrieval · 1967 · 738 citations

Computing, Computer Science, Mathematics +11

Operations Which Preserve Definability in Languages

Seymour Ginsburg, Gene F. Rose · Journal of the ACM · 1963 · 70 citations · Full text

Computing, Computer Science, Language Documentation +6

On a classification of context-free languages.

Jozef Gruska · Kybernetika · 1967 · 36 citations

Computing, Computer Science, Natural Language Processing +9