@incollection{JEDP_1986____A9_0,
     author = {Gerd Grubb},
     title = {Singular perturbations and parameter-dependent pseudo-differential boundary problems},
     booktitle = {},
     series = {Journ\'ees \'equations aux d\'eriv\'ees partielles},
     eid = {9},
     pages = {1--7},
     publisher = {\'Ecole polytechnique},
     year = {1986},
     zbl = {0607.35012},
     mrnumber = {874551},
     language = {en},
     url = {https://proceedings.centre-mersenne.org/item/JEDP_1986____A9_0/}
}