@article{MAN_1979__242_163273,
     author = {Herbert Leinfelder},
     title = {A {Geometrie} {Proof} of the {Spectral} {Theorem} for {Unbounded} {Self-Adjoint} {Operators.}},
     journal = {Mathematische Annalen},
     pages = {85--96},
     publisher = {mathdoc},
     volume = {242},
     year = {1979},
     zbl = {0388.47011},
     url = {http://geodesic.mathdoc.fr/item/MAN_1979__242_163273/}
}