Apakov, Yusufjon P. P., and Stasys Rutkauskas. “On a Boundary Value Problem to Third Order PDE With Multiple Characteristics”. Nonlinear Analysis: Modelling and Control 16, no. 3 (July 25, 2011): 255–269. Accessed May 6, 2024. https://www.journals.vu.lt/nonlinear-analysis/article/view/14092.