@Article{ mag03, author = { Magnani, Valentino }, title = { The coarea formula for real-valued Lipschitz maps on stratified groups }, journal = { Math. Nachr. }, year = { 2005 }, volume = { 278 }, number = { 14 }, pages = { 1689-1705 }, URL = { http://cvgmt.sns.it/paper/717/ }, note = { cvgmt preprint} }