Astrika G, Panggayuh A, Mardiyanti T. The Effect Of Birthing Ball On The Duration Of Active Phase In Primigravida At Pmb Yulis Indriana, Malang. JPK [Internet]. 2019Oct.29 [cited 2025Oct.24];8(2):164-75. Available from: https://ojs.poltekkes-malang.ac.id/jpk/article/view/1021