@article{DAN_1976_229_5_a6,
     author = {A. M. Revyakin},
     title = {A certain construction in categories of combinatorial geometries and mappings},
     journal = {Doklady Akademii Nauk},
     pages = {1055--1058},
     year = {1976},
     volume = {229},
     number = {5},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1976_229_5_a6/}
}