The play is complete in itself and perfectly charming, nevertheless I ventured to add an epilog.
1. Extended Programming In LOGic. PROLOG with several AND's having different time constraints.
["Epilog: A Language for Extended Programming in Logic", A. Porto in Implementations of Prolog, J.A. Campbell ed, Ellis Horwood 1984].
2. A data-driven PROLOG, with both AND parallelism and OR parallelism. ["EPILOG = PROLOG + Data Flow", M.J. Wise, SIGPLAN Noices 17:80-86 (1982)].