@article{MZ_1991__207_2_174285,
     author = {Zongzhu Lin},
     title = {Extensions between simple modules for {Frobenius} kernels.},
     journal = {Mathematische Zeitschrift},
     pages = {485--500},
     publisher = {mathdoc},
     volume = {207},
     number = {2},
     year = {1991},
     zbl = {0810.20035},
     url = {http://geodesic.mathdoc.fr/item/MZ_1991__207_2_174285/}
}