Sivakumar Nagarajan Scott D. Goodwin Abdul Sattar John Thornton On Dual Encodings for Non-binary Constraint Satisfaction Problems. 531-536 http://link.springer.de/link/service/series/0558/bibs/1894/18940531.htm 2000 conf/cp/2000 CP db/conf/cp/cp2000.html#NagarajanGST00