@article{DMSMF_2008_2008_1_a0,
     author = {Daoui, A. and  Hachadi, H. and  Zerouali, E. H.},
     title = {Spectral invariance under operator equations},
     journal = {Disertaciones del Seminario de Matem\'aticas Fundamentales},
     pages = {1-11},
     publisher = {mathdoc},
     volume = {39},
     year = {2008},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/DMSMF_2008_2008_1_a0/}
}