Obukhovskiĭ, Valeri, Pietro Zecca, and Victor G. Zvyagin. “Optimal Feedback Control in the Problem of the Motion of a Viscoelastic Fluid”. Topological Methods in Nonlinear Analysis 23, no. 2 (June 1, 2004): 323–337. Accessed July 22, 2024. https://apcz.umk.pl/TMNA/article/view/TMNA.2004.014.