@article{MM2_1996__90_2_156206,
     author = {Markus Poppenberg},
     title = {Negative results on the {Nash-Moser} theorem for {K\"othe} sequences spaces and for spaces of ultradifferentiable functions.},
     journal = {Manuscripta mathematica},
     pages = {465--478},
     publisher = {mathdoc},
     volume = {90},
     number = {2},
     year = {1996},
     zbl = {0871.46003},
     url = {http://geodesic.mathdoc.fr/item/MM2_1996__90_2_156206/}
}