@article{MZM_1981_30_5_a10,
     author = {P. I. Sovertkov},
     title = {Christoffel problem in {pseudo-Euclidean} space $E_{n-1,1}$},
     journal = {Matemati\v{c}eskie zametki},
     pages = {737--748},
     publisher = {mathdoc},
     volume = {30},
     number = {5},
     year = {1981},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1981_30_5_a10/}
}