@article{01016572, title = {Hopf-bifurcation in systems with spherical symmetry. I: Invariant tori.}, journal = {Documenta Mathematica}, volume = {2}, year = {1997}, pages = {61-113}, zbl = {0873.58020}, language = {en}, url = {http://dml.mathdoc.fr/item/01016572} }
Leis, Christian. Hopf-bifurcation in systems with spherical symmetry. I: Invariant tori.. Documenta Mathematica, Tome 2 (1997) pp. 61-113. http://gdmltest.u-ga.fr/item/01016572/