@article{DAN_1972_204_3_a4,
     author = {M. I. Kanovitch},
     title = {On the universality of strongly undecidable sets},
     journal = {Doklady Akademii Nauk},
     pages = {533--535},
     publisher = {mathdoc},
     volume = {204},
     number = {3},
     year = {1972},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1972_204_3_a4/}
}