@incollection{AST_1992__210__197_0,
     author = {Hislop, Peter D.},
     title = {Singular perturbations of {Dirichlet} and {Neumann} domains and resonances for obstacle scattering},
     booktitle = {M\'ethodes semi-classiques Volume 2 - Colloque international (Nantes, juin 1991)},
     series = {Ast\'erisque},
     pages = {197--216},
     publisher = {Soci\'et\'e math\'ematique de France},
     number = {210},
     year = {1992},
     language = {en},
     url = {http://www.numdam.org/item/AST_1992__210__197_0/}
}