@article{10_4064_fm_65_2_169_192,
     author = {Kei\^o Nagami},
     title = {\ensuremath{\Sigma}-spaces},
     journal = {Fundamenta Mathematicae},
     pages = {169--192},
     publisher = {mathdoc},
     volume = {65},
     number = {2},
     year = {1969},
     doi = {10.4064/fm-65-2-169-192},
     language = {fr},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/fm-65-2-169-192/}
}