SidenkoN. R. “Averaging of the Dirichlet Problem for a Special Hyperbolic Kirchhoff Equation”. Ukrains’kyi Matematychnyi Zhurnal 58, no. 2 (February 25, 2006): 236–249. Accessed November 22, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/3449.