@article{DAN_1973_209_4_a3,
     author = {A. K. Guts},
     title = {On mappings of families of sets},
     journal = {Doklady Akademii Nauk},
     pages = {773--774},
     publisher = {mathdoc},
     volume = {209},
     number = {4},
     year = {1973},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1973_209_4_a3/}
}