L. J. Alias and S.-E. Koh, “Remarks on Compact Spacelike Hypersurfaces in de Sitter Space with Constant Higher Order Mean Curvature,” Journal of Geometry and Physics, Vol. 39, No. 1, 2001, pp. 45-49.
http://dx.doi.org/10.1016/S0393-0440(00)00073-5

has been cited by the following article:

• TITLE: A New Characterization of Totally Umbilical Hypersurfaces in de Sitter Space

  AUTHORS: Linfen Cao, Guodong Xu, Zhaohui Dai

  KEYWORDS: de Sitter Space; Spacelike Hypersurface; Higher Order Mean Curvatures

  JOURNAL NAME: Advances in Pure Mathematics, Vol.4 No.2, February 24, 2014

  ABSTRACT: It is shown that a compact spacelike hypersurface which is contained in the chronological future (or past) of an equator of de Sitter space is a totally umbilical round sphere if the kth mean curvature function Hk is a linear combination of Hk+1,…, Hn. This is a new angle to characterize round spheres.