@article{JOLT_2003_13_1_a11,
     author = {C. Stroppel},
     title = {Homomorphisms and {Extensions} of {Principal} {Series} {Representations}},
     journal = {Journal of Lie Theory},
     pages = {193--212},
     year = {2003},
     volume = {13},
     number = {1},
     doi = {10.5802/jolt.298},
     zbl = {1026.17009},
     url = {https://jolt.centre-mersenne.org/articles/10.5802/jolt.298/}
}