The repository contains various resources related to Ungler's printing houses (Cracow 1510–1516, 1521-1536) and some other printing houses.
Some resources can be subject to different licence than the default CC0, it is always stated explicitely.
To view the DjVu files you need of course a DjVu viewer, I recommend the original one: https://djvu.sourceforge.net/djview4.html
To browse the index file you need the djview4poliqarp program: https://github.com/jsbien/djview-poliqarp_fork.
See also
https://github.com/jsbien/repertuarXVI (access granted on request)
https://github.com/jsbien/Rubricella (access granted on request)
the publications listed at https://www.zotero.org/jsbien.
See also:
Andrzej Tomaszewski: A work done for a historical edition for the Polish National Library. A presentation given during LETTRA 2018 at the Jagiellonian Library in Kraków, and at BachoTex 2019.