V. M. Gorbachuk, “On solutions of parabolic and elliptic type differential equations on $(-\infty, \infty)$ in a Banach space”, MFAT, vol. 14, no. 2, pp. 177–183, Jun. 2008, Accessed: Dec. 18, 2025. [Online]. Available: https://zen.imath.kiev.ua/index.php/mfat/article/view/381