@article{AULFM_1987_02_a4,
     author = {Niewiarowski, Jerzy},
     title = {Some remarks about homeomorphisms preserving (f)-porosity},
     journal = {Acta Universitatis Lodziensis. Folia Mathematica},
     year = {1987},
     volume = {02},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/AULFM_1987_02_a4/}
}