# Percy S. F. van Keulen
**Wikidata**: [Q93234478](https://www.wikidata.org/wiki/Q93234478)  
**Source**: https://4ort.xyz/entity/percy-s-f-van-keulen


## References

1. BnF authorities
2. Integrated Authority File
3. [Source](https://viaf.org/viaf/data/viaf-20230206-links.txt.gz)
4. Virtual International Authority File
5. Catalogue of the Library of the Pontifical University of the Holy Cross
6. VIAF ID
7. [LIBRIS. 2013](https://libris.kb.se/qn25bsp81vcmrhn)