@article{MAN_1965__162_161343,
     author = {N. DUNFORD},
     title = {A {Spectral} {Theory} for {Certain} {Operators} on a {Direct} {Sum} of {Hilbert} {Spaces.}},
     journal = {Mathematische Annalen},
     pages = {294--330},
     publisher = {mathdoc},
     volume = {162},
     year = {1965},
     zbl = {0139.31202},
     url = {http://geodesic.mathdoc.fr/item/MAN_1965__162_161343/}
}