@article{01873026, title = {Homomorphisms and extensions of principal series representations.}, journal = {Journal of Lie Theory}, volume = {13}, year = {2003}, pages = {193-212}, zbl = {1026.17009}, language = {en}, url = {http://dml.mathdoc.fr/item/01873026} }
Stroppel, Catharina. Homomorphisms and extensions of principal series representations.. Journal of Lie Theory, Tome 13 (2003) pp. 193-212. http://gdmltest.u-ga.fr/item/01873026/