1. Bar-Hillel, Y., Perles, M., Shamir, E.: On formal properties of simple phrase structure grammars. Zeitschrift für Phonologie, Sprachwissenschaft und Kommunikationsforschung 14, 113–124 (1961)
2. Basten, H.J.S.: The usability of ambiguity detection methods for context-free grammars. In: Johnstone, A., Vinju, J. (eds.) Eighth Workshop on Language Descriptions, Tools, and Applications (LDTA 2008), Budapest, Hungary (April 2008)
3. Lecture Notes in Computer Science;C. Brabrand,2007
4. Hopcroft, J., Ullman, J.: Introduction to Automata Theory, Languages, and Computation. Addison-Wesley, Reading (1979)
5. Culik II, K., Cohen, R.S.: LR-regular grammars - an extension of LR(k) grammars. Journal of Computer and System Sciences 7(1), 66–96 (1973)