@article{KUTGS_1976_9_a10,
     author = {A. S. Podkovyrin},
     title = {Theory of analytic surfaces of a biaffine {space.~I}},
     journal = {Trudy Geometricheskogo Seminara},
     pages = {77--87},
     year = {1976},
     volume = {9},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/KUTGS_1976_9_a10/}
}