Berezhnoi, M. A. “Small Oscillations of a Viscous Incompressible Fluid With a Large Number of Small Interacting Particles in the Case of Their Surface Distribution”. Ukrains’kyi Matematychnyi Zhurnal, Vol. 61, no. 3, Mar. 2009, pp. 302-21, https://umj.imath.kiev.ua/index.php/umj/article/view/3021.