@article{CRMATH_2003__336_10_817_0,
     author = {Bonfiglioli, Andrea and Uguzzoni, Francesco},
     title = {Some non-existence results for critical equations on step-two stratified groups},
     journal = {Comptes Rendus. Math\'ematique},
     pages = {817--822},
     publisher = {Elsevier},
     volume = {336},
     number = {10},
     year = {2003},
     doi = {10.1016/S1631-073X(03)00193-6},
     language = {en},
     url = {http://www.numdam.org/articles/10.1016/S1631-073X(03)00193-6/}
}