Abstract：Let Mn be a compact and oriented hyper-surface without boundary in the unit hyperbolic space form Hn+1. Assume that the i-mean curvature Hi>0,i=1,2,…,r for some integer r(1≤r≤n-1) and that Hr is constant, We proved that Mn is totally umbilical if the Gauss image of Mn is contained in an open hemisphere.
王琪. 双曲空间中全脐超曲面与高斯映照像[J]. 浙江大学学报（理学版）, 2016, 43(5): 537-538.
WANG Qi. Totally umbilical hyper-surfaces of the hyperbolic space and the Gauss image. Journal of ZheJIang University(Science Edition), 2016, 43(5): 537-538.
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