@article{ETNA_1995__3__a4,
     author = {Varga,  Richard S. and Krautstengl,  Alan},
     title = {Minimal {Gerschgorin} sets for partitioned matrices. {III:} {Sharpness} of boundaries and monotonicity as a function of the partition},
     journal = {Electronic transactions on numerical analysis},
     pages = {83--95},
     year = {1995},
     volume = {3},
     zbl = {0857.15009},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ETNA_1995__3__a4/}
}