@article{MAN_1991__290_4_164813,
     author = {P. Mammone and J.-P. Tignol and A. Wadsworth},
     title = {Fields of characteristic 2 with prescribed u-invariants.},
     journal = {Mathematische Annalen},
     pages = {109--128},
     publisher = {mathdoc},
     volume = {290},
     number = {4},
     year = {1991},
     zbl = {0713.12002},
     url = {http://geodesic.mathdoc.fr/item/MAN_1991__290_4_164813/}
}