Jin-yi Cai, Xi Chen, Pinyan Lu. Graph Homomorphisms with Complex Values: A Dichotomy Theorem. In Samson Abramsky, Cyril Gavoille, Claude Kirchner, Friedhelm Meyer auf der Heide, Paul G. Spirakis, editors, Automata, Languages and Programming, 37th International Colloquium, ICALP 2010, Bordeaux, France, July 6-10, 2010, Proceedings, Part I. Volume 6198 of Lecture Notes in Computer Science, pages 275-286, Springer, 2010. [doi]
Abstract is missing.