@article{CMUC_1990_31_3_a1,
     author = {Bartol, Wiktor},
     title = {Weak subalgebra lattices of monounary partial algebras},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {411--414},
     year = {1990},
     volume = {31},
     number = {3},
     mrnumber = {1078474},
     zbl = {0711.08007},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMUC_1990_31_3_a1/}
}