Zhang, Guang Yuan. “The Numbers of Periodic Orbits Hidden at Fixed Points of $n$-Dimensional Holomorphic Mappings (II)”. Topological Methods in Nonlinear Analysis 33, no. 1 (March 1, 2009): 65–83. Accessed July 22, 2024. https://apcz.umk.pl/TMNA/article/view/TMNA.2009.006.