@article{CMUC_1968__9_4_a9,
     author = {Bukovsk\'y, Lev},
     title = {$\nabla$-model and distributivity in {Boolean} algebras},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {595--612},
     publisher = {mathdoc},
     volume = {09},
     number = {4},
     year = {1968},
     mrnumber = {0262129},
     zbl = {0211.01701},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMUC_1968__9_4_a9/}
}