YES ---- CR(R) ---- R : left-linear, C : CR and CP-closing, and Cdup/R : SN R: f(g(x)) -> f(h(x,x)) g(a()) -> g(g(a())) h(a(),a()) -> g(g(a())) CP(R): f(g(g(a()))) -> f(h(a(),a())) critical-pair-closing system C: h(a(),a()) -> g(g(a())) CR(C): see below. ---- CR(R) ---- R : left-linear, C : CR and CP-closing, and Cdup/R : SN R: h(a(),a()) -> g(g(a())) CP(R): critical-pair-closing system C: CR(C): see below. ---- CR(R) ---- R is empty.