@incollection{JEDP_2006____A4_0,
     author = {Fouassier, Elise},
     title = {High frequency limit of {Helmholtz} equations: the case of a~discontinuous index},
     booktitle = {},
     series = {Journ\'ees \'equations aux d\'eriv\'ees partielles},
     eid = {4},
     pages = {1--19},
     publisher = {Groupement de recherche 2434 du CNRS},
     year = {2006},
     doi = {10.5802/jedp.31},
     language = {en},
     url = {http://www.numdam.org/articles/10.5802/jedp.31/}
}