@article{KuehneHuitemaCarle2012,
  author    = {Ralph K{\"u}hne and George Huitema and George Carle},
  title     = {Charging and billing in modern communications networks a comprehensive survey of the state of the art and future requirements},
  journal   = {IEEE communications surveys \& tutorials},
  volume    = {14},
  number    = {1},
  pages     = {170 -- 192},
  doi       = {10.1109/SURV.2011.122310.000084},
  year      = {2012},
}