@article{10_4064_cm_57_1_29_33,
     author = {Peter R. Jones},
     title = {Exchange properties and basis properties for closure operators},
     journal = {Colloquium Mathematicum},
     pages = {29--33},
     publisher = {mathdoc},
     volume = {57},
     number = {1},
     year = {1989},
     doi = {10.4064/cm-57-1-29-33},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/cm-57-1-29-33/}
}