@article{JRAM_1968__232_150881,
     author = {R.G. Douglas},
     title = {Structure theory for operators. {I.}},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {180--193},
     publisher = {mathdoc},
     volume = {232},
     year = {1968},
     zbl = {0164.44301},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1968__232_150881/}
}