# RETRACTED ARTICLE: A multi-scale and rotation-invariant phase pattern (MRIPP) and a stack of restricted Boltzmann machine (RBM) with preprocessing for facial expression classification

> Research article (Journal of Ambient Intelligence and Humanized Computing, 2020) · cited 31× · AI/ML

**Wikidata**: [openalex:W3087556850](https://www.wikidata.org/wiki/openalex:W3087556850)  
**Source**: https://4ort.xyz/entity/retracted-article-a-multi-scale-and-rotation-invariant-phase-pattern-mripp-and-a-stack-of-restricted-boltzmann-machine-r