@article{AULFM_1991_04_a1,
     author = {Jasku{\l}a, Janusz and Szkopi\'nska, Bo\.zena},
     title = {On the symmetric continuity},
     journal = {Acta Universitatis Lodziensis. Folia Mathematica},
     publisher = {mathdoc},
     volume = {04},
     year = {1991},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/AULFM_1991_04_a1/}
}