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.
{(ftp://nexus.yorku.ca/pub/scheme/scm/bevan.shar)}
["Constraint Programming Languages - Their Specification and
Generation", W. Leler, A-W 1988, ISBN 0-201-06243-7].