# hafnium

> chemical element with symbol Hf and atomic number 72

**Wikidata**: [Q1119](https://www.wikidata.org/wiki/Q1119)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Hafnium)  
**Source**: https://4ort.xyz/entity/hafnium


## References

1. [Source](http://www.cdc.gov/niosh/npg/npgd0309.html)
2. hafnium. Global Substance Registration System
3. [CAS Common Chemistry](https://commonchemistry.cas.org/detail?cas_rn=7440-58-6)
4. HAFNIUM. PubChem
5. ChEBI release 2020-09-01
6. Atomic weights of the elements 2009 (IUPAC Technical Report)
7. [Source](https://www.cns11643.gov.tw/wordView.jsp?ID=151148)
8. Freebase Data Dumps. 2013
9. Hafnium. ChemSpider
10. hafnium atom. ChEBI
11. Integrated Authority File
12. [Source](https://www.britannica.com/science/hafnium)
13. HAFNIUM, ELEMENTAL. Hazardous Substances Data Bank. 2019
14. [Source](https://iupac.org/standard-atomic-weight-of-hafnium-revised/)
15. Hafnium. ECHA Substance Infocard database
16. UMLS 2023
17. Mapping file of InChIStrings, InChIKeys and DTXSIDs for the EPA CompTox Dashboard
18. National Library of Israel
19. KBpedia
20. GF WordNet
21. [OpenAlex](https://docs.openalex.org/download-snapshot/snapshot-data-format)
22. UniChem