A Quadruple Integral Involving the Legendre Function Pn(x) of the First Kind: Derivation and Evaluation. Eur. J. Pure Appl. Math. [Internet]. 2022 Jul. 31 [cited 2024 Apr. 28];15(3):1113-9. Available from: https://ejpam.com/index.php/ejpam/article/view/4237