A combinatorial theorem for a symmetric triangulation of the sphere $S^2$
Wladyslaw Kulpa, Marian Turzański · Czech digital mathematics library · 2001
We shall prove a combinatorial lemma from which it follows that the set g !(0) of zeros of a continuous and odd function g : S 2 -> R, g( -x) = -g(x), from the 2-dimensional sphere S 2 contains a symmetric component.