Yong-Quan Shen, Young-Kyun Sim, Junsu Bae, In-Ju Bang, Jae-Pil Seo. "Differences in the relationship among grit, self-regulation, competition preparation, and sport confidence across performance levels: a multi-group analysis." Scientific Reports (2025). https://doi.org/10.1038/s41598-025-16448-w