AndrusyakI. V., and FilevychP. V. 2016. “The Coefficients of Power Expansion and $a$-Points of an Entire Function With Borel Exceptional Value”. Ukrains’kyi Matematychnyi Zhurnal 68 (2), 147-55. https://umj.imath.kiev.ua/index.php/umj/article/view/1829.