@article{Graf,
  author    = {Johannes Graf},
  title     = {Uhrenindustrie im 20. Jahrhundert},
  series = {Jahresschrift / Deutsche Gesellschaft f{\"u}r Chronometrie},
  volume    = {58.2019},
  issn      = {1617-0113},
  pages     = {240 -- 259},
  language  = {de}
}