Torkestani, Javad Akbari, and Mohammad Reza Meybodi. “A New Vertex Coloring Algorithm Based on Variable Action-Set Learning Automata”. COMPUTING AND INFORMATICS, vol. 29, no. 3, Jan. 2012, pp. 447-66, https://www.cai.sk/ojs/index.php/cai/article/view/93.