Virchenko, N.O., and A.M. Ponomarenko. “New Generalizations of the Zeta-Function and the Tricomi Funation”. Reports of the National Academy of Sciences of Ukraine, no. 12 (December 28, 2016): 5–11. Accessed June 20, 2026. https://nasu-periodicals.org.ua/index.php/dp/article/view/12893.