@article{MAN_1964__155_161196,
     author = {E.-A. Behrens},
     title = {Unendliche quasi-einreihige {Halbgruppen.}},
     journal = {Mathematische Annalen},
     pages = {343--368},
     publisher = {mathdoc},
     volume = {155},
     year = {1964},
     zbl = {0126.26704},
     url = {http://geodesic.mathdoc.fr/item/MAN_1964__155_161196/}
}