@article{IM_1989__95_3_143669,
     author = {C. Okonek and A. de Van de Ven},
     title = {...-type-invariants associated to {PU(2)-bundles} and the differentiable structure of {Barlow's} surface.},
     journal = {Inventiones mathematicae},
     pages = {601--614},
     year = {1989},
     volume = {95},
     number = {3},
     zbl = {0691.57007},
     url = {http://geodesic.mathdoc.fr/item/IM_1989__95_3_143669/}
}