@article{JRAM_1960__203_150419,
     author = {Otton Martin Nikodym},
     title = {Contribution to the theory of maximal, normal operators in a separable and complete {Hilbert-Hermite-space.} {II.}},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {90--109},
     publisher = {mathdoc},
     volume = {203},
     year = {1960},
     zbl = {0178.49003},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1960__203_150419/}
}