@article{CMH_1986__61_140065, author = {R. Parimala and M. Ojanguren}, title = {Symplectic bundles over affine surfaces.}, journal = {Commentarii mathematici Helvetici}, pages = {491--500}, publisher = {mathdoc}, volume = {61}, year = {1986}, zbl = {0598.14006}, url = {http://geodesic.mathdoc.fr/item/CMH_1986__61_140065/} }