Serov, N. I., and R. M. Cherniga. “Lie Symmetries, Q-Conditional Symmetries, and Exact Solutions of Nonlinear Systems of Diffusion-Convection Equations”.
Ukrains’kyi Matematychnyi Zhurnal 55, no. 10 (October 25, 2003): 1340–1355. Accessed April 7, 2025.
https://umj.imath.kiev.ua/index.php/umj/article/view/4006.