Rubber friction directional asymmetryA. Tiwari, L. Dorogin, B. Steenwyk, A. Warhadpande, M. Motamedi, G. Fortunato, V. Ciaravola and B. N. J. PerssonEPL, 116 6 (2016) 66002DOI: https://doi.org/10.1209/0295-5075/116/66002