arXiv · 1507.07018
A proof based on the Chern-Gauss-Bonnet Theorem is given to Hopf Theorem concerning the degree of the Gauss map of a hypersurface in $\mathbb{R}^n$.
Daniel Cibotaru. 2015-07-24. A short proof of a Theorem by Hopf. https://arxiv.org/abs/1507.07018
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