@article{MZ_1958__69_169726,
     author = {Horst Leptin},
     title = {Zur {Reduktionstheorie} {Hilbertscher} {R\"aume.}},
     journal = {Mathematische Zeitschrift},
     pages = {40--58},
     publisher = {mathdoc},
     volume = {69},
     year = {1958},
     zbl = {0078.10401},
     url = {http://geodesic.mathdoc.fr/item/MZ_1958__69_169726/}
}