# Karl Ostertag
**Wikidata**: [Q94833025](https://www.wikidata.org/wiki/Q94833025)  
**Source**: https://4ort.xyz/entity/karl-ostertag-q94833025


## References

1. Integrated Authority File
2. Czech National Authority Database
3. Catalog of the German National Library
4. Discogs
5. BnF authorities