@article{Borowiecki:1993,
  author  = "M. Borowiecki and E. Drgas-Burchardt",
  title   = "Classes of chromatically unique graphs",
  journal = "Discrete Mathematics",
  volume  = "Vol. 111",
  number  = "no 1-3",
  pages   = "71--75",
  year    = "1993",
}