Require Export Undecidability.PCP.Definitions.

(* Problems concerning string rewriting *)

(* Verification of PCP-Related Computational Reductions in Coq. Yannick Forster, Edith Heiter, and Gert Smolka. ITP 2018. Subdirectory `PCP`. https://ps.uni-saarland.de/extras/PCP  *)

About SR.  (* reachability in string rewriting systems *)
About SRH. (* reachability of empty string in string rewriting systems *)
