@article{10_4064_cm_42_1_367_375,
     author = {Lucjan Szamko{\l}owicz},
     title = {On problems related to characteristic vertices of graphs},
     journal = {Colloquium Mathematicum},
     pages = {367--375},
     publisher = {mathdoc},
     volume = {42},
     number = {1},
     year = {1979},
     doi = {10.4064/cm-42-1-367-375},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/cm-42-1-367-375/}
}