@conference{Montanari91a,
author = "Ugo Montanari and Francesca Rossi",
booktitle = "Proc. of the $8^th$ international conference on
                   Logic Programming",
editor = "Koichi Furukawa",
keywords = "CSP, PLC, coherence locale, coherence globale",
pages = "223-237",
publisher = "The MIT Press",
title = "{P}erfect {R}elaxation in {C}onstraint {L}ogic {P}rogramming",
year = "1991",
}