@article{SM_1990_66_2_a8,
     author = {G. D. Berishvili},
     title = {Symplectic structure on {a~Grassmannian} fibration},
     journal = {Sbornik. Mathematics},
     pages = {439--446},
     publisher = {mathdoc},
     volume = {66},
     number = {2},
     year = {1990},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_1990_66_2_a8/}
}