@article{SF_1983__26_134613,
     author = {G. Rod\'e},
     title = {Differentiability of a convex semigroup on {IRm.}},
     journal = {Semigroup forum},
     pages = {317--322},
     publisher = {mathdoc},
     volume = {26},
     year = {1983},
     zbl = {0509.47053},
     url = {http://geodesic.mathdoc.fr/item/SF_1983__26_134613/}
}