Fel’shtyn, A., and V. Pilyugina. “Topology of an Attraction Domain, Dynamical Zeta Functions and Reidemeister Torsion”. Topological Methods in Nonlinear Analysis, vol. 9, no. 2, June 1997, pp. 259-78, https://apcz.umk.pl/TMNA/article/view/TMNA.1997.013.