Abstract
A simple proof of a theorem of H. Hopf [1], via Morse theory, is given.
Open Access
On a theorem of H. Hopf
Received01 Feb 1989
Revised09 Mar 1990
Copyright
Copyright © 1990 Hindawi Publishing Corporation. This is an open access article distributed under the
Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.