Zunnunov, R.T., and A.A. Ergashev. “A Problem With Shift for a Mixed-Type Model Equation of the Second Kind in an Unbounded Domain”. Bulletin of the Karaganda University. Mathematics Series 106, no. 2 (June 30, 2022): 202–207. Accessed September 4, 2025. http://mts.buketov.edu.kz/index.php/mathematics-vestnik/article/view/539.