%0 Journal Article %A Landsberg, Joseph M. %T Exterior differential systems, Lie algebra cohomology, and the rigidity of homogenous varieties %J Archivum mathematicum %D 2008 %P 419-447 %V 44 %N 5 %I mathdoc %U http://geodesic.mathdoc.fr/item/ARM_2008__44_5_a7/ %G en %F ARM_2008__44_5_a7