A Prolog exteNsioN with AND-parallelism, {doN' t-kNow NoNdetermiNism} aNd iNterprocess commuNicatioN usiNg syNchroNous eveNt goals aNd distributed backtrackiNg. ["Delta-Prolog: A Distributed Logic ProgrammiNg LaNguage", L.M. Pereira et al, INtl CoNf 5th GeN Comp Sys, Nov 1984].