Wulandari, Anggrawati, et al. “Effectiveness of Walking Sport to Sleep Quality of Pregnant Women on The Third Trimester in Silir Village, Wates, Kediri”. Journal for Quality in Women’s Health, vol. 1, no. 1, Mar. 2018, pp. 27-32, https://www.jqwh.org/index.php/JQWH/article/view/5.