@article{IM2_1977_11_5_a2,
     author = {Vik. S. Kulikov},
     title = {Degenerations of $K3$ surfaces and {Enriques} surfaces},
     journal = {Izvestiya. Mathematics},
     pages = {957--989},
     year = {1977},
     volume = {11},
     number = {5},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_1977_11_5_a2/}
}