@article{Stephan2014,
  author    = {Christoph A. Stephan},
  title     = {A dark sector extension of the almost-commutative standard model},
  journal   = {International journal of modern physics : A, Particles and fields, gravitation, cosmology, nuclear physics},
  volume    = {29},
  number    = {1},
  doi       = {10.1142/S0217751X14500055},
  year      = {2014},
}