Risdiana, Nurvita, Syahruramdhani Syahruramdhani, and Armain Suwitno. 2021. “The Physical Fitness Level, Heart Rate, and Heart Rate Recovery Among Adolescent Smokers and Non-Smokers”. Open Access Macedonian Journal of Medical Sciences 9 (T4):101-5. https://doi.org/10.3889/oamjms.2021.5805.