@article{MR_1988_34_a0,
     author = {Mohammad S. Khan and  Salvatore Sessa},
     title = {Nonconvex sets and fixed points},
     journal = {M\ensuremath{\alpha}\ensuremath{\theta}\ensuremath{\eta}\ensuremath{\mu}\ensuremath{\alpha}\ensuremath{\tau}\ensuremath{\iota}\ensuremath{\kappa}\ensuremath{\acute\eta} E\ensuremath{\pi}\ensuremath{\iota}\ensuremath{\theta}\ensuremath{\varepsilon}\ensuremath{\acute\omega}\ensuremath{\rho}\ensuremath{\eta}\ensuremath{\sigma}\ensuremath{\eta}},
     pages = {1--4},
     year = {1988},
     volume = {34},
     language = {gr},
     url = {http://geodesic.mathdoc.fr/item/MR_1988_34_a0/}
}