Palágyi, Kálmán. “How Sufficient Conditions Are Related for Topology-Preserving Reductions”. Acta Cybernetica 23, no. 3 (January 1, 2018): 939-958. Accessed November 21, 2024. https://cyber.bibl.u-szeged.hu/index.php/actcybern/article/view/3986.