Handayani, E. S., Setyoningrum, R. A., & Wungu, C. D. K. (2022). Efficacy of vitamin D supplementation on the incidence of recurrent pneumonia in children: A systematic review and meta-analysis study. International Journal of Health Sciences, 6(S4), 2267–2280. https://doi.org/10.53730/ijhs.v6nS4.7179