%0 Journal Article %A Lu, Zhiqin %T On the rigidity of horizontal slices. %J Portugaliae mathematica %D 2002 %P 409-433 %V 59 %N 4 %I mathdoc %U http://geodesic.mathdoc.fr/item/PORMA_2002__59_4_50604/ %G en %F PORMA_2002__59_4_50604