2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/140728In 2002 Jurdzinski and Lorys settled a long-standing conjecture that palindromes are not a Church-Rosser language. Their proof required a sophisticated theory about computation graphs of 2-stack automata. We present their proof in terms of 1-tape Turing machines.We also provide an alternative proof of Buntrock and Otto's result that the set of non-square bitstrings, which is context-free, is not Church-Rosser.15 pagesLogic in Computer ScienceF.4.2; F.4.3text