@article{DAN_1969_188_5_a6,
     author = {V. K. Ionin},
     title = {Riemannian spaces with {Euclidean} isoperimetric inequality},
     journal = {Doklady Akademii Nauk},
     pages = {990--992},
     publisher = {mathdoc},
     volume = {188},
     number = {5},
     year = {1969},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1969_188_5_a6/}
}