Bertrand

(Named after the British mathematician Bertrand Russell

(1872-1970)). Wm. Leler. Rule-based specification language

based on augmented term rewriting. Used to implement

constraint languages. The user must explicitly specify the

tree-search and the constraint propagation.

.

["Constraint Programming Languages - Their Specification and

Generation", W. Leler, A-W 1988, ISBN 0-201-06243-7].