@article {MR1736394,
    AUTHOR = {G{\"o}pfert, A. and Tammer, Chr. and Z{\u{a}}linescu, C.},
     TITLE = {On the vectorial {E}keland's variational principle and minimal
              points in product spaces},
   JOURNAL = {Nonlinear Anal.},
  FJOURNAL = {Nonlinear Analysis. Theory, Methods \& Applications. An
              International Multidisciplinary Journal. Series A: Theory and
              Methods},
    VOLUME = {39},
      YEAR = {2000},
    NUMBER = {7, Ser. A: Theory Methods},
     PAGES = {909--922},
      ISSN = {0362-546X},
     CODEN = {NOANDD},
   MRCLASS = {49J53 (90C29)},
  MRNUMBER = {MR1736394 (2001a:49019)},
MRREVIEWER = {Sehie Park},
       DOI = {10.1016/S0362-546X(98)00255-7},
       URL = {http://dx.doi.org/10.1016/S0362-546X(98)00255-7},
}