Zhang, Mengtian, et al. “Analysis of the Optimal Timing for NIPT and the Detection of Fetal Abnormalities Based on Cluster Analysis and Gradient Boosting Techniques”. International Journal of Public Health and Medical Research, vol. 6, no. 2, Feb. 2026, pp. 62-71, https://doi.org/10.62051/ijphmr.v6n2.07.