@incollection {MR956283,
    AUTHOR = {Kawski, Matthias},
     TITLE = {An angular open mapping theorem},
 BOOKTITLE = {Analysis and optimization of systems ({A}ntibes, 1988)},
    SERIES = {Lecture Notes in Control and Inform. Sci.},
    VOLUME = {111},
     PAGES = {361--371},
 PUBLISHER = {Springer},
   ADDRESS = {Berlin},
      YEAR = {1988},
   MRCLASS = {49E15 (93D15)},
  MRNUMBER = {MR956283 (89m:49068)},
MRREVIEWER = {Jean-Pierre Aubin},
}