@article{MAN_1905__60_158200,
     author = {H.E. Hawkes},
     title = {On {Quaternion} {Number-Systems}},
     journal = {Mathematische Annalen},
     pages = {437--447},
     publisher = {mathdoc},
     volume = {60},
     year = {1905},
     zbl = {36.0282.02},
     url = {http://geodesic.mathdoc.fr/item/MAN_1905__60_158200/}
}