SaloT. M., and SkaskivO. B. “Entire Dirichlet Series of Rapid Growth and New Estimates for the Measure of Exceptional Sets in Theorems of the Wiman–Valiron Type”. Ukrains’kyi Matematychnyi Zhurnal, Vol. 53, no. 6, June 2001, pp. 830-9, https://umj.imath.kiev.ua/index.php/umj/article/view/4303.