Koonsiripaiboon, J., and S. Tantracheewathorn. “Prevalence and Risk Factors of Osteopenia of Prematurity of Very Low Birth Weight Infants at Faculty of Medicine Vajira Hospital”. Vajira Medical Journal : Journal of Urban Medicine, vol. 64, no. 6, Dec. 2020, pp. 371-80, doi:10.14456/vmj.2020.36.