# Katian

> second stage and age of the Upper Ordovician Series / Late Ordovician Epoch

**Wikidata**: [Q1736601](https://www.wikidata.org/wiki/Q1736601)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Katian)  
**Source**: https://4ort.xyz/entity/katian


## References

1. International Chronostratigraphic Chart 2013/01
2. [Source](https://stratigraphy.org/chart)
3. [Source](https://stratigraphy.org/gssps/#ordovician)
4. Freebase Data Dumps. 2013
5. [The Global Stratotype Section and Point (GSSP) for the base of the Katian Stage of the Upper Ordovician Series at Black Knob Ridge, Southeastern Oklahoma, USA](https://doi.org/10.18814/epiiugs/2007/v30i4/002)
6. [Source](https://stratigraphy.org/gssps/katian)