@article{RM_2012_67_2_a4,
     author = {Yu. S. Ledyaev and J. S. Treiman},
     title = {Sub- and supergradients of envelopes, semicontinuous closures, and limits of sequences of functions},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {345--373},
     publisher = {mathdoc},
     volume = {67},
     number = {2},
     year = {2012},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/RM_2012_67_2_a4/}
}