Pannavira, & Hermawan, A. (2026). Multimodal Wearable-Based Stress Detection Using Machine Learning: A Systematic Review of Validation Protocols and Generalization Gaps (2021 – 2025). Ultimatics : Jurnal Teknik Informatika, 17(2), 203–213. https://doi.org/10.31937/ti.v17i2.4488