@incollection{iiasa14151,
          volume = {111},
          series = {Lecture Notes in Control and Information Sciences},
       booktitle = {Analysis and Optimization of Systems},
          editor = {A. Bensoussan and J.L. Lions},
         address = {Germany},
           title = {Set valued solutions to control problems and their approximations},
       publisher = {Springer Berlin Heidelberg},
            year = {1988},
             doi = {doi:10.1007/BFb0042263},
           pages = {775--785},
             url = {https://pure.iiasa.ac.at/id/eprint/14151/},
            isbn = {978-3-540-39161-6},
          author = {Kurzhanski, A. B. and Valyi, I.}
}