# Doppler effect

> frequency change of a wave for observer relative to its source

**Wikidata**: [Q76436](https://www.wikidata.org/wiki/Q76436)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Doppler_effect)  
**Source**: https://4ort.xyz/entity/doppler-effect


## References

1. A Short History of Astronomy
2. Integrated Authority File
3. [Nuovo soggettario](https://thes.bncf.firenze.sbn.it/termine.php?id=15585)
4. Nuovo soggettario
5. Freebase Data Dumps. 2013
6. [Registros de autoridad de "Materia" de la Biblioteca Nacional de España. Spain open data portal](https://www.bne.es/media/datosgob/catalogo-autoridades/materia/materia-UTF8.zip)
7. BBC Things
8. Quora
9. National Library of Israel
10. [OpenAlex](https://docs.openalex.org/download-snapshot/snapshot-data-format)