@article{IM2_1998_62_4_a6,
     author = {V. N. Solov'ev},
     title = {The subdifferential and the directional derivatives of the maximum of a~family of convex functions},
     journal = {Izvestiya. Mathematics },
     pages = {807--832},
     publisher = {mathdoc},
     volume = {62},
     number = {4},
     year = {1998},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_1998_62_4_a6/}
}