@misc{Kepler_Johannes_(1571-1630)_Ioannis,
 author={Kepler, Johannes (1571-1630)},
 howpublished={online},
 publisher={Gottfried Tambach},
 language={lat},
 title={Ioannis Kepleri S.C. Maiest. Mathematici Strena Seu De Niue Sexangula},
 type={starodruk},
}