Anwar, K. K., Yustiari, Y. ., Hasmia Naningsi, & Asi, M. (2023). The Effect of Counter Pressure and Birthball on The Time of The First Stage of Labor and Prevention of Perineal Rupture. Poltekita : Jurnal Ilmu Kesehatan, 17(3), 647–654. https://doi.org/10.33860/jik.v17i3.3042