@article{10_4064_sm_48_3_251_255,
     author = {\v{S}tefan Schwabik},
     title = {A remark on the d-characteristic and the $d_{\ensuremath{\Xi}}$-characteristic of linear operators in a {Banach} space},
     journal = {Studia Mathematica},
     pages = {251--255},
     publisher = {mathdoc},
     volume = {48},
     number = {3},
     year = {1973},
     doi = {10.4064/sm-48-3-251-255},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/sm-48-3-251-255/}
}