@article{10_21136_CPM_1980_118058,
     author = {Dr\'abek, Pavel},
     title = {Ranges of $a$-homogeneous operators and their perturbations},
     journal = {\v{C}asopis pro p\v{e}stov\'an{\'\i} matematiky},
     pages = {167--183},
     publisher = {mathdoc},
     volume = {105},
     number = {2},
     year = {1980},
     doi = {10.21136/CPM.1980.118058},
     mrnumber = {573109},
     zbl = {0427.47048},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/CPM.1980.118058/}
}