@article{DAN_1981_260_5_a8,
     author = {V. G. Kanovei and A. V. Ostrovsky},
     title = {On {non-Borel} $F_\parallel$-sets},
     journal = {Doklady Akademii Nauk},
     pages = {1061--1064},
     publisher = {mathdoc},
     volume = {260},
     number = {5},
     year = {1981},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1981_260_5_a8/}
}