@article{10_4064_fm_92_2_91_94,
     author = {Jussi Ketonen},
     title = {On the existence of {P-points} in the {Stone-\v{C}ech} compactification of integers},
     journal = {Fundamenta Mathematicae},
     pages = {91--94},
     publisher = {mathdoc},
     volume = {92},
     number = {2},
     year = {1976},
     doi = {10.4064/fm-92-2-91-94},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/fm-92-2-91-94/}
}