@article{ETNA_2008__31__a5,
     author = {Schwetlick,  Hubert and Schreiber,  Kathrin},
     title = {A counterexample for characterizing an invariant subspace of a matrix},
     journal = {Electronic transactions on numerical analysis},
     pages = {295--305},
     year = {2008},
     volume = {31},
     zbl = {1189.65071},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ETNA_2008__31__a5/}
}