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