Crstici, Borislav, and Mihai Neagu. “Extensions of Some Finite Difference Equations for the Case of Distributions”. Anal. Numér. Théor. Approx. 11, no. 1 (August 1, 1982): 49–57. Accessed April 14, 2025. https://ictp.acad.ro/jnaat/journal/article/view/1982-vol11-nos1-2-art6.