@article{GDZPPN00228474X,
title = {On Ordered Fields and Definite Functions.},
journal = {Mathematische Annalen},
volume = {129},
year = {1955},
pages = {257-271},
zbl = {0067.01502},
url = {http://dml.mathdoc.fr/item/GDZPPN00228474X}
}
Robinson, A. On Ordered Fields and Definite Functions.. Mathematische Annalen, Tome 129 (1955) pp. 257-271. http://gdmltest.u-ga.fr/item/GDZPPN00228474X/