FilevychP. V. “An Exact Estimate for the Measure of the Exceptional Set in the Borel Relation for Entire Functions”. Ukrains’kyi Matematychnyi Zhurnal, Vol. 53, no. 2, Feb. 2001, pp. 286-8, https://umj.imath.kiev.ua/index.php/umj/article/view/4249.