@article{GDZPPN00210363X, title = {Multi-cones over Schubert varieties}, journal = {Inventiones mathematicae}, volume = {88}, year = {1987}, pages = {353-364}, zbl = {0615.14028}, url = {http://dml.mathdoc.fr/item/GDZPPN00210363X} }
Ramanathan, A.; Kempf, G.R. Multi-cones over Schubert varieties. Inventiones mathematicae, Tome 88 (1987) pp. 353-364. http://gdmltest.u-ga.fr/item/GDZPPN00210363X/