YES ---- CR(R) ---- R : left-linear, C : CR and CP-closing, and Cdup/R : SN R: h(f(f(f(h(c(),h(b(),c()))))),h(f(f(b())),b())) -> f(h(b(),f(a()))) f(c()) -> b() CP(R): critical-pair-closing system C: h(f(f(f(h(c(),h(b(),c()))))),h(f(f(b())),b())) -> f(h(b(),f(a()))) CR(C): see below. ---- CR(R) ---- R : linear and strongly closed [Huet, 1980] R: h(f(f(f(h(c(),h(b(),c()))))),h(f(f(b())),b())) -> f(h(b(),f(a()))) CP(R):