@article{MAN_1990__287_1_164693,
     author = {Stephen Halperin},
     title = {Primitive subspaces of {Hopf} algebras of finite depth.},
     journal = {Mathematische Annalen},
     pages = {387--390},
     publisher = {mathdoc},
     volume = {287},
     number = {1},
     year = {1990},
     zbl = {0687.57019},
     url = {http://geodesic.mathdoc.fr/item/MAN_1990__287_1_164693/}
}