@article{IM2_1974_8_6_a4,
     author = {N. V. Panov},
     title = {The {Gurevich} $bu$-homomorphism},
     journal = {Izvestiya. Mathematics},
     pages = {1225--1234},
     year = {1974},
     volume = {8},
     number = {6},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_1974_8_6_a4/}
}