@article{IJOPCM_2008__1_3_228476,
     author = {Saboormaleki, M.},
     title = {On the spectrum of non-selfadjoint differential operators.},
     journal = {International journal of open problems in computer science and mathematics},
     pages = {240},
     year = {2008},
     volume = {1},
     number = {3},
     zbl = {1216.47076},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IJOPCM_2008__1_3_228476/}
}