CHIP[2]
Constraint Handling In Prolog
M. Dincbas, ECRC Munich 1985
A constraint logic language which includes boolean unification and a symbolic simplex-like algorithm. It provides constraints over integers, rationals and booleans. Symbolic constraints, cumulative constraints, and update demons. CHIP introduced the domain-variable model.
"The Constraint Logic Programming Language CHIP", M. Dincbas et al, Proceedings of the 2nd International Conference on Fifth Generation Computer Systems, Tokyo (Nov 1988), pp.249-264.
"Constraint Satisfaction in Logic Programming", Van Hentenryck.