@article{MMO_1953_2_a3,
     author = {A. G. Sigalov},
     title = {Two-dimensional problems of the calculus of variations in nonparametric form},
     journal = {Trudy Moskovskogo matemati\v{c}eskogo ob\^{s}estva},
     pages = {201--233},
     publisher = {mathdoc},
     volume = {2},
     year = {1953},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MMO_1953_2_a3/}
}