Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{NUMA_1963__5_131572, author = {N.J. LEHMANN}, title = {Optimale {Eigenwerteinschlie{\ss}ungen.}}, journal = {Numerische Mathematik}, pages = {246--272}, publisher = {mathdoc}, volume = {5}, year = {1963}, url = {http://geodesic.mathdoc.fr/item/NUMA_1963__5_131572/} }
N.J. LEHMANN. Optimale Eigenwerteinschließungen.. Numerische Mathematik, Tome 5 (1963), pp. 246-272. http://geodesic.mathdoc.fr/item/NUMA_1963__5_131572/