@article{Kirch2008,
  author    = {Gottfried Kirch},
  title     = {De simplicissima quadam specie Micrometri},
  url       = {http://edoc.bbaw.de/oa/series/reSA1LVCopqgE/PDF/25N0vgP1PxMg.pdf},
  year      = {2008},
}