Bogdanskii, Yu. V. “Divergence Theorem in the $L_2$ -Version. Application to the Dirichlet Problem”. Ukrains’kyi Matematychnyi Zhurnal 70, no. 5 (May 25, 2018): 611–624. Accessed January 27, 2026. https://umj.imath.kiev.ua/index.php/umj/article/view/1581.