Pavlenko, V. N. “Control of Singular Distributed Parabolic Systems With Discontinuous Nonlinearities”.
Ukrains’kyi Matematychnyi Zhurnal
, vol. 46, no. 6, June 1994, pp. 729–736,
https://umj.imath.kiev.ua/index.php/umj/article/view/5700
.