Pukalskyi, I. D. “Green Function of a Parabolic Boundary-Value Problem and the Optimization Problem”.
Ukrains’kyi Matematychnyi Zhurnal
, vol. 52, no. 4, Apr. 2000, pp. 567-71,
https://umj.imath.kiev.ua/index.php/umj/article/view/4448
.