@article{05346593, title = {Linear least squares with quadratic constraints.}, journal = {Divulgaciones Matem\'aticas}, volume = {15}, year = {2007}, pages = {161-177}, zbl = {1149.65030}, language = {en}, url = {http://dml.mathdoc.fr/item/05346593} }
Castillo, Zenaida. Linear least squares with quadratic constraints.. Divulgaciones Matemáticas, Tome 15 (2007) pp. 161-177. http://gdmltest.u-ga.fr/item/05346593/