Hasibuan, Ismart, M Supriatmo, A Faisal, Gabriel Panggabean, Ridwan Daulay, Zakaria Siregar, and Helmi Lubis. “Peak Expiratory Flow Rate of Primary School Children in High and Low Air Pollution Level Areas”. Paediatrica Indonesiana 43, no. 1 (September 24, 2016): 10-13. Accessed May 2, 2024. https://paediatricaindonesiana.org/index.php/paediatrica-indonesiana/article/view/650.