Belan, E. P., and O. B. Lykova. “Theorem on the Central Manifold of a Nonlinear Parabolic Equation”. Ukrains’kyi Matematychnyi Zhurnal 48, no. 8 (August 25, 1996): 1021–1036. Accessed February 17, 2026. https://umj.imath.kiev.ua/index.php/umj/article/view/5246.