@article{JOLT_2020_30_4_a11,
     author = {J. Ellegaard Andersen and J. C. Jantzen and D. Pei},
     title = {Identities for {Poincar\'e} {Polynomials} via {Kostant} {Cascades}},
     journal = {Journal of Lie Theory},
     pages = {1131--1160},
     year = {2020},
     volume = {30},
     number = {4},
     doi = {10.5802/jolt.1154},
     zbl = {1530.20117},
     url = {https://jolt.centre-mersenne.org/articles/10.5802/jolt.1154/}
}