@article{MAN_1985__271_163977,
     author = {David R. Morrison},
     title = {The {Birational} {Geometry} of {Surfaces} with {Rational} {Double} {Points.}},
     journal = {Mathematische Annalen},
     pages = {415--438},
     publisher = {mathdoc},
     volume = {271},
     year = {1985},
     zbl = {0539.14008},
     url = {http://geodesic.mathdoc.fr/item/MAN_1985__271_163977/}
}