@article{UZKU_1955_115_14_a3,
     author = {A. Z. Petrov},
     title = {On gravitational fields of a~simple type with real stationary curvatures},
     journal = {U\v{c}\"enye zapiski Kazanskogo universiteta. Seri\^a Fiziko-matemati\v{c}eskie nauki},
     pages = {41--52},
     publisher = {mathdoc},
     volume = {115},
     number = {14},
     year = {1955},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/UZKU_1955_115_14_a3/}
}