The Rewrite Rule Laboratory ( RRL). Forked from https://www.cs.cmu.edu/afs/cs/project/ai-repository/ai/areas/reasonng/atp/systems/rrl/0.html, since the FTP Server "ftp://cs.uiowa.edu/pub/hzhang/rrl/rrl.tar.Z" doesn't respind anymore. - View it on GitHub