@article{05241627, title = {Some sharp }, journal = {SIGMA. Symmetry, Integrability and Geometry: Methods and Applications [electronic only]}, volume = {3}, year = {2007}, zbl = {1141.15026}, language = {en}, url = {http://dml.mathdoc.fr/item/05241627} }
Balinsky, Alexander; Ryan, John. Some sharp . SIGMA. Symmetry, Integrability and Geometry: Methods and Applications [electronic only], Tome 3 (2007) . http://gdmltest.u-ga.fr/item/05241627/