@article{ZAA_2000__19_3_48989,
     author = {D'Aniello, Emma and Darji, U.B.},
     title = {On the existence of  functions with perfect level sets.},
     journal = {Zeitschrift f\"ur Analysis und ihre Anwendungen},
     pages = {847--852},
     publisher = {mathdoc},
     volume = {19},
     number = {3},
     year = {2000},
     zbl = {0976.26002},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ZAA_2000__19_3_48989/}
}