A PTAS for k-means clustering based on weak coresets.

Dan Feldman Morteza Monemizadeh Christian Sohler A PTAS for k-means clustering based on weak coresets. 11-18 2007 conf/compgeom/2007 Symposium on Computational Geometry http://doi.acm.org/10.1145/1247069.1247072 db/conf/compgeom/compgeom2007.html#FeldmanMS07