Vuković, Mirjana, Emil Ilić-Georgijević, and Olivera Stevanović. 2024. “On an Application of Parseval’s Formula to Problems of $G_\theta^\varkappa$-Summability of Eigenfunction Expansion of the Laplacian Operator”. Sarajevo Journal of Mathematics 12 (2):267-76. https://doi.org/10.5644/SJM.12.2.12.