# Characterizing facial expressions by grammars of action unit sequences – A first investigation using ABL

> Research article (Information Sciences, 2015) · cited 10× · AI/ML

**Wikidata**: [openalex:W1848463718](https://www.wikidata.org/wiki/openalex:W1848463718)  
**Source**: https://4ort.xyz/entity/characterizing-facial-expressions-by-grammars-of-action-unit-sequences-a-first-investigation-using-abl