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As of FEBio version 1.2, two alternative formulations for sliding contact are available. The first method, which is referred to as the facet-to-facet sliding, is very similar to the formulation described above. It only differs in that it uses a Gaussian quadrature rule instead of nodal integration. Because of the more accurate integration rule, it was noted that this method in many situations was more stable and resulted in better convergence.