1. Compound and serial grammars;Abraham;Information and Control,1972
2. Three theorems on phrase-structure grammars;Landweber;Information and Control,1963
3. Grammars and Finite Automata;Marcus,1964
4. Some context-sensitive grammars;Paun;Stud. Cerc. Mat.,1974
5. Formal Languages;Salomaa,1973