MokhonkoA. Z., and MokhonkoA. A. “Malmquist Theorem for the Solutions of Differential Equations in the Vicinity of a Branching Point”. Ukrains’kyi Matematychnyi Zhurnal, Vol. 66, no. 9, Sept. 2014, pp. 1286–1290, https://umj.imath.kiev.ua/index.php/umj/article/view/2221.