@article{JRAM_1978__0303_0304_152061,
     author = {Alexander Prestel},
     title = {Remarks on the {Pythagoras} and {Hasse} number of real fields.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {284--294},
     publisher = {mathdoc},
     volume = {0303_0304},
     year = {1978},
     zbl = {0396.10013},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1978__0303_0304_152061/}
}