Takács, Péter, Csajbók, Zoltán Ernő, Mihálydeák, Tamás (2015) Boundaries of membrane in P systems relying on multiset approximation spaces in language R Annales Mathematicae et Informaticae. 44. pp. 197-210. ISSN 1787-5021 (Print), 1787-6117 (Online)