# Aptian

> fifth stage and age of the Lower Cretaceous series / Early Cretaceous epoch

**Wikidata**: [Q622265](https://www.wikidata.org/wiki/Q622265)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Aptian)  
**Source**: https://4ort.xyz/entity/aptian


## References

1. International Chronostratigraphic Chart 2013/01
2. Freebase Data Dumps. 2013
3. [OpenAlex](https://docs.openalex.org/download-snapshot/snapshot-data-format)