@article{IM_1991__106_1_143942,
     author = {N.I. Shepherd-Barron},
     title = {Geography for surfaces of general type in positive characteristic.},
     journal = {Inventiones mathematicae},
     pages = {263--274},
     publisher = {mathdoc},
     volume = {106},
     number = {1},
     year = {1991},
     zbl = {0813.14025},
     url = {http://geodesic.mathdoc.fr/item/IM_1991__106_1_143942/}
}