@article{DAN_1961_138_5_a8,
     author = {M. B. Pergamenshchikov},
     title = {Configuration of $H$~congruences},
     journal = {Doklady Akademii Nauk},
     pages = {1020--1021},
     publisher = {mathdoc},
     volume = {138},
     number = {5},
     year = {1961},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1961_138_5_a8/}
}