KoshmanenkoV. D., and KharchenkoN. V. “Invariant Points of a Dynamical System of Conflict in the Space of Piecewise-Uniformly Distributed Measures”. Ukrains’kyi Matematychnyi Zhurnal, Vol. 56, no. 7, July 2004, pp. 927–938, https://umj.imath.kiev.ua/index.php/umj/article/view/3809.