@article{10_4064_fm_99_1_73_78,
     author = {R. Freiwald},
     title = {Images of {B(k)}},
     journal = {Fundamenta Mathematicae},
     pages = {73--78},
     publisher = {mathdoc},
     volume = {99},
     number = {1},
     year = {1978},
     doi = {10.4064/fm-99-1-73-78},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/fm-99-1-73-78/}
}