# Karl Ludwig
**Wikidata**: [Q91630226](https://www.wikidata.org/wiki/Q91630226)  
**Source**: https://4ort.xyz/entity/karl-ludwig-q91630226


## References

1. [Source](https://www.biographien.ac.at/oebl/oebl_L/Ludwig_Karl_1866_1931.xml)
2. Students of the Universities of Prague 1882–1945
3. Integrated Authority File
4. Q96032572
5. Virtual International Authority File
6. [Source](https://biblio.hiu.cas.cz/authorities/133873)
7. Czech National Authority Database
8. Dictionary of Czech librarians