Zar, Vershima Daniel, et al. “EVALUATING THE WHO PEN INITIATIVE: A SYSTEMATIC REVIEW OF ITS INFLUENCE ON NON-COMMUNICABLE DISEASE AWARENESS AND PREVENTION AMONG PRIMARY HEALTHCARE WORKERS IN NIGERIA”. American Journal of Public Health and Epidemiology (AJPHE), vol. 11, no. 3, June 2025, pp. 15-32, doi:10.5281/zenodo.15690030.