@article{10_21136_MB_2019_0038_18,
     author = {Carpintero, Carlos and Guti\'errez, Alexander and Rosas, Ennis and Sanabria, Jos\'e},
     title = {A note on preservation of spectra for two given operators},
     journal = {Mathematica Bohemica},
     pages = {113--126},
     publisher = {mathdoc},
     volume = {145},
     number = {2},
     year = {2020},
     doi = {10.21136/MB.2019.0038-18},
     mrnumber = {4221824},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/MB.2019.0038-18/}
}