@article{MS2_1972__31_166269,
     author = {Arne Brondsted},
     title = {On the {Subdifferential} of the {Supremum} of {Two} {Convex} {Functions.}},
     journal = {Mathematica Scandinavica},
     pages = {225--230},
     publisher = {mathdoc},
     volume = {31},
     year = {1972},
     zbl = {0253.46101},
     url = {http://geodesic.mathdoc.fr/item/MS2_1972__31_166269/}
}