Runovskii, K.V. (1993) “A method of summation of the Fourier-Jacobi series”, Ukrains’kyi Matematychnyi Zhurnal, 45(5), pp. 676–680. Available at: https://umj.imath.kiev.ua/index.php/umj/article/view/5854 (Accessed: 26 April 2025).