# Long-run dynamics of the U.S. patent classification system

> Research article (Journal of Evolutionary Economics, 2019) · cited 36× · AI/ML

**Wikidata**: [openalex:W2592718662](https://www.wikidata.org/wiki/openalex:W2592718662)  
**Source**: https://4ort.xyz/entity/long-run-dynamics-of-the-u-s-patent-classification-system