Per Austrin, Aleksa Stankovic. Global Cardinality Constraints Make Approximating Some Max-2-CSPs Harder. In Dimitris Achlioptas, László A. Végh, editors, Approximation, Randomization, and Combinatorial Optimization. Algorithms and Techniques, APPROX/RANDOM 2019, September 20-22, 2019, Massachusetts Institute of Technology, Cambridge, MA, USA. Volume 145 of LIPIcs, Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2019. [doi]