Algebraic Informatics 8th International Conference, CAI 2019, Niš, Serbia, June 30-July 4, 2019, Proceedings - Ćirić, Miroslav; Ćirić, Miroslav; Droste, Manfred; Droste, Manfred; Pin, Jean-Éric; Pin, Jean-Éric (Springer International Publishing : Imprint: Springer, 2019)