@article{CMJ_1998__48_4_a0,
     author = {Kordula, Vladim{\'\i}r},
     title = {On the defect spectrum of an extension of a {Banach} space operator},
     journal = {Czechoslovak Mathematical Journal},
     pages = {609--616},
     publisher = {mathdoc},
     volume = {48},
     number = {4},
     year = {1998},
     mrnumber = {1658217},
     zbl = {0954.47002},
     language = {en},
     url = {https://geodesic-test.mathdoc.fr/item/CMJ_1998__48_4_a0/}
}