@article{DAN_1963_153_2_a11,
     author = {A. I. Fet},
     title = {Extremal problems for surfaces of bounded {Gaussian} curvature},
     journal = {Doklady Akademii Nauk},
     pages = {292--295},
     publisher = {mathdoc},
     volume = {153},
     number = {2},
     year = {1963},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1963_153_2_a11/}
}