@article{MZ_1989__201_4_174063,
     author = {Helmut H. Schaefer and Werner J. Ricker},
     title = {The {Uniformly} {Closed} {Algebra} {Generated} by a {Complete} {Boolean} {Algebra} of {Projections.}},
     journal = {Mathematische Zeitschrift},
     pages = {429--440},
     publisher = {mathdoc},
     volume = {201},
     number = {4},
     year = {1989},
     zbl = {0655.47038},
     url = {http://geodesic.mathdoc.fr/item/MZ_1989__201_4_174063/}
}