@article{MS2_1974__35_166393,
     author = {P. Ribenboim},
     title = {Pfister's {Dimension} and the {Level} of {Fields.}},
     journal = {Mathematica Scandinavica},
     pages = {301--308},
     publisher = {mathdoc},
     volume = {35},
     year = {1974},
     zbl = {0301.12101},
     url = {http://geodesic.mathdoc.fr/item/MS2_1974__35_166393/}
}