Siregar, Febrina, Gabriel Panggabean, Ridwan Daulay, and Helmi Lubis. 2009. “Comparison of Peak Expiratory Flow Rate (PEFR) before and After Physical Exercise in Obese and Non-Obese Children”. Paediatrica Indonesiana 49 (1), 20-4. https://doi.org/10.14238/pi49.1.2009.20-4.