Khourinisa, K., and Helmi Wardah Nasution. “The Influence Of Respiratory Relaxation Techniques On Pain Intensity In The First Stage Of Labor At The Atikah Sipolu-Polu Midwifery Clinic, Panyabungan District, Mandailing Natal Regency”. Jurnal EduHealth, vol. 13, no. 01, Aug. 2022, pp. 487-93, https://ejournal.seaninstitute.or.id/index.php/healt/article/view/4860.