Touzaline, Arezki, and Djamel Eddine Teniou. “A Quasistatic Unilateral Contact Problem With Friction for Nonlinear Elastic Materials”. Mathematical Modelling and Analysis, vol. 12, no. 4, Dec. 2007, pp. 497-14, https://doi.org/10.3846/1392-6292.2007.12.497-514.