@article{Grassmann2015,
  author    = {Peter Graßmann},
  title     = {Der Komet von 1538},
  journal   = {Villingen im Wandel der Zeit},
  series    = {und andere Villinger Wunderzeichenberichte},
  volume    = {38},
  pages     = {46 -- 49},
  doi       = {10.57962/regionalia-16821},
  year      = {2015},
}