@article{DAN_1971_198_5_a11,
     author = {A. G. Iosifyan and N. P. Konopleva},
     title = {Isoperimetric variational problems in field theory},
     journal = {Doklady Akademii Nauk},
     pages = {1036--1039},
     publisher = {mathdoc},
     volume = {198},
     number = {5},
     year = {1971},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1971_198_5_a11/}
}