@article{ELA_2006__15__a14,
     author = {Niezgoda, Marek},
     title = {Upper bounds on certain functionals defined on groups of linear operators},
     journal = {The electronic journal of linear algebra},
     pages = {191--200},
     publisher = {mathdoc},
     volume = {15},
     year = {2006},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ELA_2006__15__a14/}
}