Simbolon GAH, Sitohang NTR, Silalahi EL. Comparative Study: Yoga and Pregnancy Exercise on First Stage Pain and Length of Labor in Tapanuli Regency. jppipa, pendidikan ipa, fisika, biologi, kimia [Internet]. 2023 Oct. 25 [cited 2024 Jun. 30];9(10):7950-7. Available from: https://jppipa.unram.ac.id/index.php/jppipa/article/view/5308