@article{MS2_1956__4_165603,
     author = {SIGURDUR HELGASON},
     title = {A characterization of the intersection of {L1-spaces}},
     journal = {Mathematica Scandinavica},
     pages = {5--8},
     year = {1956},
     volume = {4},
     zbl = {0073.09101},
     url = {http://geodesic.mathdoc.fr/item/MS2_1956__4_165603/}
}