%0 Conference Paper %B Proceedings of the seventeenth annual ACM-SIAM symposium on Discrete algorithm %D 2006 %T Combination can be hard: Approximability of the unique coverage problem %A Demaine,E. D %A Hajiaghayi, Mohammad T. %A Feige,U. %A Salavatipour,M. R %B Proceedings of the seventeenth annual ACM-SIAM symposium on Discrete algorithm %P 162 - 171 %8 2006/// %G eng