@incollection{JEDP_1983____A17_0,
     author = {Grisvard, Pierre},
     title = {Diagonalisation d'op\'erateurs non-autoadjoints et s\'eparation des variables},
     booktitle = {},
     series = {Journ\'ees \'equations aux d\'eriv\'ees partielles},
     eid = {17},
     pages = {1--13},
     publisher = {Ecole polytechnique},
     year = {1983},
     mrnumber = {84f:35107},
     zbl = {0528.47029},
     language = {fr},
     url = {http://archive.numdam.org/item/JEDP_1983____A17_0/}
}