Kulinich , G.L. and Mynbaeva , M.M. (1992) “Space averaging in parabolic equations ”, Ukrains’kyi Matematychnyi Zhurnal, 44(4), pp. 561–564. Available at: https://umj.imath.kiev.ua/index.php/umj/article/view/7901 (Accessed: 6 December 2025).