Bulatov, A., & Jeavons, P. (2000). Tractable constraints closed under a binary operation. Oxford University Computing Laboratory.
Chicago-viite (17. p.)Bulatov, A., ja P. Jeavons. Tractable Constraints Closed Under a Binary Operation. Oxford University Computing Laboratory, 2000.
MLA-viite (9. p.)Bulatov, A., ja P. Jeavons. Tractable Constraints Closed Under a Binary Operation. Oxford University Computing Laboratory, 2000.
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