@article{MZM_1976_20_1_a11,
     author = {L. I. Vorob'eva},
     title = {Estimate of the upper bound on the {Gaussian} curvature of certain surfaces with boundary},
     journal = {Matemati\v{c}eskie zametki},
     pages = {113--120},
     publisher = {mathdoc},
     volume = {20},
     number = {1},
     year = {1976},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1976_20_1_a11/}
}