Azagra, D. .; Ferrera, J. . Inf-Convolution and Regularization of Convex Functions on Riemannian Manifolds of Nonpositive Curvature. Rev. mat. complut. 2006, 19 ,2, 323-345. https://doi.org/10.5209/rev_REMA.2006.v19.n2.16592.