@article{ZNSL_1991_191_a9,
     author = {N. A. Karpenko},
     title = {About codimension 3 cycles on a projective quadric},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {114--123},
     year = {1991},
     volume = {191},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1991_191_a9/}
}