@article{NUMA_1966__9_131739,
     author = {F. ROBERT},
     title = {Recherche d'une {M-matrice} parmi les minorantes d'un op\'erateur lin\'eaire.},
     journal = {Numerische Mathematik},
     pages = {189--199},
     publisher = {mathdoc},
     volume = {9},
     year = {1966},
     zbl = {0156.16206},
     url = {http://geodesic.mathdoc.fr/item/NUMA_1966__9_131739/}
}