# allowed units constraint

> type of constraint for Wikidata properties: used to specify that only listed units may be used

**Wikidata**: [Q21514353](https://www.wikidata.org/wiki/Q21514353)  
**Source**: https://4ort.xyz/entity/allowed-units-constraint


## References

1. [Source](https://raw.githubusercontent.com/wikimedia/mediawiki-extensions-WikibaseQualityConstraints/dd6d6f25d094b1f0fe2cae7a47dac2f02e842c30/extension.json)
2. [Source](https://raw.githubusercontent.com/OpenRefine/OpenRefine/master/extensions/wikidata/src/org/openrefine/wikidata/qa/WikidataConstraintFetcher.java)