@article{1077294537, author = {Geiges, Hansj\"org}, title = {Symplectic structures on $T^2$ -bundles over $T^2$}, journal = {Duke Math. J.}, volume = {68}, number = {1}, year = {1992}, pages = { 539-555}, language = {en}, url = {http://dml.mathdoc.fr/item/1077294537} }
Geiges, Hansjörg. Symplectic structures on $T^2$ -bundles over $T^2$. Duke Math. J., Tome 68 (1992) no. 1, pp. 539-555. http://gdmltest.u-ga.fr/item/1077294537/