@article{CMH_1984__59_139962,
     author = {Anthony Bak and Ulf Rehmann},
     title = {K2-analogs of {Hasse's} norm theorems.},
     journal = {Commentarii mathematici Helvetici},
     pages = {1--11},
     publisher = {mathdoc},
     volume = {59},
     year = {1984},
     zbl = {0539.12007},
     url = {http://geodesic.mathdoc.fr/item/CMH_1984__59_139962/}
}