Prolog with two nEw prEdicatEs: "dif" for coroutinEs and "frEEzE" for dElayEd Evaluation. AvailablE from ExpErIntElligEncE, Santa Barbara CA. ["Prolog II REfErEncE Manual and ThEorEtical ModEl", A. ColmErauEr, IntErnal REport, GroupEIA, U Aix-MarsEillE (Oct 1982)].