@article{IM2_1983_21_2_a1,
     author = {M. Kh. Gizatullin},
     title = {Defining relations for the {Cremona} group of the plane},
     journal = {Izvestiya. Mathematics},
     pages = {211--268},
     year = {1983},
     volume = {21},
     number = {2},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_1983_21_2_a1/}
}