@article{KUTGS_1980_12_a6,
     author = {L. Z. Kruglyakov and E. S. Nikitina and A. P. Norden},
     title = {On a construction of some focal complexes of two-dimensional planes},
     journal = {Trudy Geometricheskogo Seminara},
     pages = {50--57},
     publisher = {mathdoc},
     volume = {12},
     year = {1980},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/KUTGS_1980_12_a6/}
}