1. Atanassov K (1986) Intuitionistic fuzzy sets. Fuzzy Sets Syst 20:87–96
2. Atanassov K, Stoeva S (1984) Intuitionistic $$L-$$fuzzy sets. In: Trappl, R. (ed.) Cybernetics and Systems Research 2, pp. 539–540. Elsevier, North-Holland
3. Blizard WD (1989) Multiset theory. Notre Dame J Form L 30:36–66
4. Csuhajvarjú E, Martín-Vide C, Mitrana V (2000) Multiset automata. Workshop on Membrane Computing, pp.69-83, Springer, Berlin, Heidelberg
5. Ciobanu G, Gontineac M (2007) Networks of Mealy Multiset Automata. International Workshop Automata for Cellular and Molecular Computing, MTA SZTAKI, Budapest, pp 52–63