@article{IM2_1990_35_3_a6,
     author = {V. V. Nikulin},
     title = {Del~Pezzo surfaces with log-terminal {singularities.~III}},
     journal = {Izvestiya. Mathematics },
     pages = {657--675},
     publisher = {mathdoc},
     volume = {35},
     number = {3},
     year = {1990},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_1990_35_3_a6/}
}