Filevych, P. V., and M. M. Sheremeta. “On the Regular Variation of Main Characteristics of an Entire Function”. Ukrains’kyi Matematychnyi Zhurnal 55, no. 6 (June 25, 2003): 840-849. Accessed May 13, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/3958.