@article{10_4064_sm191_3_2,
     author = {S. Rolewicz},
     title = {On smooth points of boundaries of open sets},
     journal = {Studia Mathematica},
     pages = {211--214},
     year = {2009},
     volume = {191},
     number = {3},
     doi = {10.4064/sm191-3-2},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/sm191-3-2/}
}