@article{KYB_1992__28_1_a0, author = {Kramosil, Ivan}, title = {An alternative approach to rough sets}, journal = {Kybernetika}, pages = {--25}, publisher = {mathdoc}, volume = {28}, number = {1}, year = {1992}, mrnumber = {1159871}, zbl = {0749.04006}, language = {en}, url = {http://geodesic.mathdoc.fr/item/KYB_1992__28_1_a0/} }