TY  - JOUR
AU  - Fine, Benjamin
TI  - Sum of Squares Rings
JO  - Canadian journal of mathematics
PY  - 1977
SP  - 155
EP  - 160
VL  - 29
IS  - 1
UR  - http://geodesic.mathdoc.fr/articles/10.4153/CJM-1977-014-3/
DO  - 10.4153/CJM-1977-014-3
ID  - 10_4153_CJM_1977_014_3
ER  -