@article{CRMATH_2022__360_G5_513_0,
     author = {Mandel, Rainer and Moitier, Zo{\"\i}s and Verf\"urth, Barbara},
     title = {Nonlinear {Helmholtz} equations with sign-changing diffusion coefficient},
     journal = {Comptes Rendus. Math\'ematique},
     pages = {513--538},
     publisher = {Acad\'emie des sciences, Paris},
     volume = {360},
     number = {G5},
     year = {2022},
     doi = {10.5802/crmath.322},
     language = {en},
     url = {http://archive.numdam.org/articles/10.5802/crmath.322/}
}