Daniel Winckler: De opio tractatus, in quo simul liber de opio D. Joh. Freitagii examinatur (Lipsiae : Henningus Grossius 1635)
- Digitized
> Österreichische Nationalbibliothek
> Google Books (Original from Österreichische Nationalbibliothek, digitized 14 May 2013)
> HATHI Trust | Google Books (Original from Princeton University, digitized 29 April 2011) - Bibliogrpahic reference: VD17 39:115734X
- Entry in Wiener Chinabibliographie