@article{DMGT_2013_33_1_a17,
     author = {Skupie\'n, Zdzis{\l}aw},
     title = {Sums of {Powered} {Characteristic} {Roots} {Count} {Distance-Independent} {Circular} {Sets}},
     journal = {Discussiones Mathematicae. Graph Theory},
     pages = {217--229},
     publisher = {mathdoc},
     volume = {33},
     number = {1},
     year = {2013},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/DMGT_2013_33_1_a17/}
}