1.
Ramos MVM, Almeida JCB, Moreira N, de Queiroz RJGB. Formalization of the pumping lemma for context-free languages. JFR [Internet]. 2016 Jan. 1 [cited 2024 Nov. 21];9(2):53-68. Available from: https://jfr.unibo.it/article/view/5595