How slow is the <i>k</i>-means method?

David Arthur Sergei Vassilvitskii How slow is the <i>k</i>-means method? 144-153 2006 conf/compgeom/2006 Symposium on Computational Geometry http://doi.acm.org/10.1145/1137856.1137880 db/conf/compgeom/compgeom2006.html#ArthurV06