Meier, H. A., P. Steinmann, and E. Kuhl. 2019. “Towards Multiscale Computation of Confined Granular Media: Contact Forces, Stresses and Tangent Operators”. Technische Mechanik - European Journal of Engineering Mechanics 28 (1):32-42. https://journals.ub.ovgu.de/index.php/techmech/article/view/825.