Lestari, Retno, et al. “Hubungan Kejadian Depresi Dan Insomnia Pada Lansia Di Panti Werdha Tresno Mukti Turen Malang”. Journal of Holistic Nursing Science, vol. 1, no. 1, Jan. 2014, pp. 32-42, https://coba.unimma.ac.id/nursing/article/view/424.