@article{10_4064_ap_19_2_117_121,
     author = {D. Przeworska-Rolewicz and S. Rolewicz},
     title = {On d-characteristic and $d_\ensuremath{\Xi}$-characteristic of linear operators},
     journal = {Annales Polonici Mathematici},
     pages = {117--121},
     publisher = {mathdoc},
     volume = {19},
     number = {2},
     year = {1967},
     doi = {10.4064/ap-19-2-117-121},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/ap-19-2-117-121/}
}