@article{MABA_1987_1_1_a3,
     author = {G. Isac},
     title = {A {Fixed} {Point} {Theorem.} {Application} to {Ershov's} {Optimization} {Problem} (in {French)}},
     journal = {Mathematica balkanica},
     pages = {33},
     publisher = {mathdoc},
     volume = {1},
     number = {1},
     year = {1987},
     url = {http://geodesic.mathdoc.fr/item/MABA_1987_1_1_a3/}
}