Parlog
Clark & Gregory, Imperial College 1983. An AND-parallel Prolog, with guards and committed choice nondeterminism (don't care nondeterminism). Shallow backtracking only.
Implementations: MacParlog and PC-Parlog from Parallel Logic Programming Ltd., Box 49 Twickenham TW2 5PH, UK.
ftp://ftp.inria.fr/lang/Parlog.tar.Z. E-mail: <parlog@doc.ic.ac.uk>.
["Parlog: A Parallel Logic Programming Language", K.L. Clark and S. Gregory, Imperial College, London, May 1983]. ("Parlog83", in which the ouput mechanism was assignment).
["Parallel Logic Programming in PARLOG, The Language and Its Implementation", S. Gregory, A-W 1987]. ("Parlog86", in which the output mechanism was unification, as in GHC). (See Strand).