1. Parsing, vol. 1 of The Theory of Parsing, Translation and Compiling;Aho,1972
2. On formal properties of simple phrase structure grammars;Bar-Hillel,1964
3. S.A. Cook, Path systems and language recognition, in: ACM Symposium on Theory of Computing, 1970, pp. 70–72
4. Efficient Parallel Algorithms;Gibbons,1988
5. Introduction to Formal Language Theory;Harrison,1978