@article{MZ_1988__199_1_173967,
     author = {R.W. Cross},
     title = {Properties of {Some} {Norm} {Related} {Functions} of {Unbounded} {Linear} {Operators.}},
     journal = {Mathematische Zeitschrift},
     pages = {285--302},
     publisher = {mathdoc},
     volume = {199},
     number = {1},
     year = {1988},
     zbl = {0639.47009},
     url = {http://geodesic.mathdoc.fr/item/MZ_1988__199_1_173967/}
}