@article{GDZPPN002353776, title = {The Pythagorean closure of fields.}, journal = {Mathematica Scandinavica}, volume = {38}, year = {1976}, pages = {177-191}, zbl = {0339.12101}, url = {http://dml.mathdoc.fr/item/GDZPPN002353776} }
Griffin, Malcolm P. The Pythagorean closure of fields.. Mathematica Scandinavica, Tome 38 (1976) pp. 177-191. http://gdmltest.u-ga.fr/item/GDZPPN002353776/