@article{SEDP_1991-1992____A12_0,
     author = {Lerner, Nicolas},
     title = {A non solvable operator satisfying condition ($\Psi $)},
     journal = {S\'eminaire \'Equations aux d\'eriv\'ees partielles (Polytechnique) dit aussi "S\'eminaire Goulaouic-Schwartz"},
     note = {talk:12},
     pages = {1--22},
     publisher = {Ecole Polytechnique, Centre de Math\'ematiques},
     year = {1991-1992},
     language = {en},
     url = {http://www.numdam.org/item/SEDP_1991-1992____A12_0/}
}