@article{AUCMP_2005__46_2_a11,
     author = {Piper, Greg},
     title = {Regular closure and corresponding ${\Cal P}_K \lambda$ versions of $\diamondsuit$ and $\clubsuit$},
     journal = {Acta Universitatis Carolinae. Mathematica et Physica},
     pages = {67--76},
     publisher = {mathdoc},
     volume = {46},
     number = {2},
     year = {2005},
     mrnumber = {2194048},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/AUCMP_2005__46_2_a11/}
}