@article{PORMA_1994__51_1_47641,
     author = {Borges, Carlos R.},
     title = {A study of -spaces and -spaces.},
     journal = {Portugaliae mathematica},
     pages = {109--117},
     publisher = {mathdoc},
     volume = {51},
     number = {1},
     year = {1994},
     zbl = {0861.54012},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PORMA_1994__51_1_47641/}
}