# Sonja Niederacher

> Austrian historian

**Wikidata**: [Q106902627](https://www.wikidata.org/wiki/Q106902627)  
**Source**: https://4ort.xyz/entity/sonja-niederacher


## References

1. Integrated Authority File
2. Lexikon der österreichischen Provenienzforschung
3. Leopold Museum Defends Against Restitution Claims
4. [Source](https://www.leopoldmuseum.org/en/research/provenance-research/joint-provenance-research)
5. [Source](https://www.sothebys.com/en/auctions/ecatalogue/2015/impressionist-modern-art-evening-sale-l15006/lot.26.html)