@article{AA_1995_7_1_a1,
     author = {N. Andruskiewitsch and J. Devoto},
     title = {Extensions of {Hopf} algebras},
     journal = {Algebra i analiz},
     pages = {22--61},
     publisher = {mathdoc},
     volume = {7},
     number = {1},
     year = {1995},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/AA_1995_7_1_a1/}
}