Voir la notice de l'article provenant de la source Math-Net.Ru
@article{TRSPY_1973_132_a14, author = {J. W. S. Cassels}, title = {On sums of squares}, journal = {Informatics and Automation}, pages = {114--117}, publisher = {mathdoc}, volume = {132}, year = {1973}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/TRSPY_1973_132_a14/} }
J. W. S. Cassels. On sums of squares. Informatics and Automation, Proceedings of the international conference on number theory, Tome 132 (1973), pp. 114-117. http://geodesic.mathdoc.fr/item/TRSPY_1973_132_a14/