Heidi E. Dixon Matthew L. Ginsberg Eugene M. Luks Andrew J. Parkes Generalizing Boolean Satisfiability II: Theory. 481-534 2004 22 J. Artif. Intell. Res. (JAIR) http://dx.doi.org/10.1613/jair.1555 db/journals/jair/jair22.html#DixonGLP04