Shuchi Chawla Robert Krauthgamer Ravi Kumar Yuval Rabani D. Sivakumar On the Hardness of Approximating Multicut and Sparsest-Cut. 94-114 2006 15 Computational Complexity 2 http://dx.doi.org/10.1007/s00037-006-0210-9 db/journals/cc/cc15.html#ChawlaKKRS06