@article{PORMA_1979__38_1-2_115380,
     author = {Cousot, Patrick and Cousot, Radhia},
     title = {A constructive characterization of the lattices of all retractions, preclosure, quasi-closure and closure operators on a complete lattice},
     journal = {Portugaliae mathematica},
     pages = {185--198},
     publisher = {mathdoc},
     volume = {38},
     number = {1-2},
     year = {1979},
     mrnumber = {0682367},
     zbl = {0503.06008},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PORMA_1979__38_1-2_115380/}
}