@article{CMH_1961__36_139235,
     author = {Oskar Weber},
     title = {\"Uber die {Reduktion} und die {Darstellungen} positiver quatern\"arer quadratischer {Formen.}},
     journal = {Commentarii mathematici Helvetici},
     pages = {181--213},
     publisher = {mathdoc},
     volume = {36},
     year = {1961},
     zbl = {0112.27701},
     url = {http://geodesic.mathdoc.fr/item/CMH_1961__36_139235/}
}