Ying Chen, Laura D. Kubzansky, Eric S. Kim, Hayami Koga, Koichiro Shiba, R. Noah Padgett, Renae Wilkinson, Byron R. Johnson, Tyler J. VanderWeele. "The distribution of optimism across sociodemographic groups in 22 countries." Scientific Reports, 2025. doi:10.1038/s41598-024-77257-1