Exploring the Containment Hierarchy of Subrings over Rings ℤ 2 to ℤ 9 in Two-Dimensional Cellular Automata. - Velvet Alexander; Ummity Srinivasa Rao; Kedar Shinde; Jayaram Balabaskaran; R. J. Hari; Asif Islam; Aqdus Bin Bari (Complex Syst., 2026)