@article{1183745249, author = {Pentus, Mati}, title = {Product-Free Lambek Calculus and Context-Free Grammars}, journal = {J. Symbolic Logic}, volume = {62}, number = {1}, year = {1997}, pages = { 648-660}, language = {en}, url = {http://dml.mathdoc.fr/item/1183745249} }
Pentus, Mati. Product-Free Lambek Calculus and Context-Free Grammars. J. Symbolic Logic, Tome 62 (1997) no. 1, pp. 648-660. http://gdmltest.u-ga.fr/item/1183745249/