@article{CRMATH_2002__334_2_105_0,
     author = {Gir\~ao, Pedro M.},
     title = {A sharp inequality for {Sobolev} functions},
     journal = {Comptes Rendus. Math\'ematique},
     pages = {105--108},
     publisher = {Elsevier},
     volume = {334},
     number = {2},
     year = {2002},
     doi = {10.1016/S1631-073X(02)02215-X},
     language = {en},
     url = {http://archive.numdam.org/articles/10.1016/S1631-073X(02)02215-X/}
}