@article{GDZPPN001165402, title = {On Smallest Isolated Gerschgorin Disks for Eigenvalues.}, journal = {Numerische Mathematik}, volume = {7}, year = {1965}, pages = {171-175}, zbl = {0148.01703}, url = {http://dml.mathdoc.fr/item/GDZPPN001165402} }
TODD, J. On Smallest Isolated Gerschgorin Disks for Eigenvalues.. Numerische Mathematik, Tome 7 (1965) pp. 171-175. http://gdmltest.u-ga.fr/item/GDZPPN001165402/