Wira Ekdeni Aifa, Fajar Sari Tanberika, and Sumandar. “Effect Of Counterpressure With Birth Ball On Reduction Of Labor Pain In First Stage ”. Science Midwifery 10, no. 3 (August 24, 2022): 2353–2358. Accessed April 19, 2026. https://www.midwifery.iocspublisher.org/index.php/midwifery/article/view/652.