Equivalence of Functions Represented by Simple Context-Free Grammars with Output. - Cédric Bastien; Jurek Czyzowicz; Wojciech Fraczak; Wojciech Rytter (Developments in Language Theory, 2006)

Prime normal form and equivalence of simple grammars. - Cédric Bastien; Jurek Czyzowicz; Wojciech Fraczak; Wojciech Rytter (Theor. Comput. Sci., 2006)

Reducing Simple Grammars: Exponential against Highly-Polynomial Time in Practice. - Cédric Bastien; Jurek Czyzowicz; Wojciech Fraczak; Wojciech Rytter (Int. J. Found. Comput. Sci., 2007)

Equivalence of simple functions. - Cédric Bastien; Jurek Czyzowicz; Wojciech Fraczak; Wojciech Rytter (Theor. Comput. Sci., 2007)