@article{CC_2005_34_3_a8,
     author = {Frankowska, H.},
     title = {Optimal synthesis via superdifferentials of value function},
     journal = {Control and Cybernetics},
     pages = {787--803},
     year = {2005},
     volume = {34},
     number = {3},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CC_2005_34_3_a8/}
}