# Early stages of proportional reasoning: a cross-sectional study with 5- to 9-year-olds

> Research article (European Journal of Psychology of Education, 2019) · cited 26× · AI/ML

**Wikidata**: [openalex:W2969521249](https://www.wikidata.org/wiki/openalex:W2969521249)  
**Source**: https://4ort.xyz/entity/early-stages-of-proportional-reasoning-a-cross-sectional-study-with-5-to-9-year-olds