P. Ryckelynck and L. Smoch, “On the functional equation αu + C ⋆ (χu) = f”, NWEJM, no. 4, pp. 1–20, Nov. 2017, Accessed: Oct. 18, 2024. [Online]. Available: https://nwejm.univ-lille.fr/index.php/nwejm/article/view/42