Protsakh, N. P. “Inverse Problem for a Semilinear Ultraparabolic Equation With Unknown Right-Hand Side”. Ukrains’kyi Matematychnyi Zhurnal 66, no. 3 (March 25, 2014): 333–348. Accessed June 16, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/2136.