Nasution, Siti Saidah, Erniyati Erniyati, and Hariati Hariati. “Effectiveness of Progressive Muscle Relaxation on The Complete Opening Time During Normal Labor”. Open Access Macedonian Journal of Medical Sciences 8, no. B (August 20, 2020): 608–611. Accessed May 6, 2024. https://oamjms.eu/index.php/mjms/article/view/4145.