Dhanuk, B. B., K. Pudasainee, H. P. Lamichhane, and R. P. Adhikari. “Dirac Delta Function from Closure Relation of Orthonormal Basis and Its Use in Expanding Analytic Functions”. Journal of Nepal Physical Society 6, no. 2 (December 31, 2020): 158–163. Accessed November 23, 2024. https://nepjol.info./index.php/JNPhysSoc/article/view/34872.