GorshkovA. I. “On Solvability of the Problem Without Initial Conditions for Strongly Parabolic Systems in a Non-Cylindrical Domain”. Ukrains’kyi Matematychnyi Zhurnal, Vol. 23, no. 4, June 1971, pp. 520-5, https://umj.imath.kiev.ua/index.php/umj/article/view/8586.