%0 Journal Article %A Sharp, R. %T Sector estimates for Kleinian groups. %J Portugaliae mathematica %D 2001 %P 461-471 %V 58 %N 4 %I mathdoc %U http://geodesic.mathdoc.fr/item/PORMA_2001__58_4_51502/ %G en %F PORMA_2001__58_4_51502