@misc{_Regnum,
 howpublished={online},
 publisher={Homann J. B.},
 language={lat},
 type={mapa},
 title={Regnum Borussiae [...] geographice cum vicinis regionibus adumbratum a Joh. Baptista Homanno},
 keywords={Polska 18w., Prusy 18w.},
}