@article{10_4064_fm_138_1_23_26,
     author = {Szymon Plewik},
     title = {Ideals of the second category},
     journal = {Fundamenta Mathematicae},
     pages = {23--26},
     publisher = {mathdoc},
     volume = {138},
     number = {1},
     year = {1991},
     doi = {10.4064/fm-138-1-23-26},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/fm-138-1-23-26/}
}