@inproceedings{hilário2010a,
title={A HOPF THEOREM FOR AMBIENT SPACES OF DIMENSIONS HIGHER THAN THREE},
author={Hilário Alencar, Manfredo do Carmo, and Renato Tribuzy},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20160911204258077065810},
booktitle={Journal of Differential Geometry},
volume={84},
number={1},
pages={1-17},
year={2010},
}
Hilário Alencar, Manfredo do Carmo, and Renato Tribuzy. A HOPF THEOREM FOR AMBIENT SPACES OF DIMENSIONS HIGHER THAN THREE. 2010. Vol. 84. In Journal of Differential Geometry. pp.1-17. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20160911204258077065810.