The aim of this paper is to describe the set of periods of a Morse-Smale diffeomorphism of the two-dimensional sphere according to its homotopy class. The main tool for proving this is the Lefschetz fixed point theory.
@article{bwmeta1.element.bwnjournal-article-doi-10_4064-cm110-2-10, author = {Juan Luis Garc\'\i a Guirao and Jaume Llibre}, title = {Periods of Morse-Smale diffeomorphisms of S2}, journal = {Colloquium Mathematicae}, volume = {111}, year = {2008}, pages = {477-483}, zbl = {1132.37015}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-cm110-2-10} }
Juan Luis García Guirao; Jaume Llibre. Periods of Morse-Smale diffeomorphisms of 𝕊². Colloquium Mathematicae, Tome 111 (2008) pp. 477-483. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-cm110-2-10/