Improper colouring of (random) unit disk graphs

@article{Kang2008ImproperCO,
  title={Improper colouring of (random) unit disk graphs},
  author={Ross J. Kang and Tobias Mueller and Jean-S{\'e}bastien Sereni},
  journal={Discrete Mathematics},
  year={2008},
  volume={308},
  pages={1438-1454}
}
For any graph G, the k-improper chromatic number χ(G) is the smallest number of colours used in a colouring of G such that each colour class induces a subgraph of maximum degree k. We investigate χ for unit disk graphs and random unit disk graphs to generalise results of [24, 22] and [23].