@article{DMGT_2006_26_2_a7,
     author = {Zverovich, Igor},
     title = {On a perfect problem},
     journal = {Discussiones Mathematicae. Graph Theory},
     pages = {273--277},
     publisher = {mathdoc},
     volume = {26},
     number = {2},
     year = {2006},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/DMGT_2006_26_2_a7/}
}