@article{AIHPC_1988__5_4_323_0, author = {Mancini, Giovanni and Musina, Roberta}, title = {Holes and obstacles}, journal = {Annales de l'I.H.P. Analyse non lin\'eaire}, pages = {323--345}, publisher = {Gauthier-Villars}, volume = {5}, number = {4}, year = {1988}, zbl = {0666.35039}, mrnumber = {963103}, language = {en}, url = {http://archive.numdam.org/item/AIHPC_1988__5_4_323_0/} }