@article{MAN_1904__58_158126,
     author = {H.E. Hawkes},
     title = {Enumeration of {Non-Quaternion} {Number-Systems}},
     journal = {Mathematische Annalen},
     pages = {361--379},
     publisher = {mathdoc},
     volume = {58},
     year = {1904},
     zbl = {35.0224.01},
     url = {http://geodesic.mathdoc.fr/item/MAN_1904__58_158126/}
}