Sinambela, Yefty Feniester, and Hesti Asriwandari. “Informal Economic Activities of the Elderly in Pekanbaru City”. QISTINA: Jurnal Multidisiplin Indonesia 3, no. 1 (June 1, 2024): 809–817. Accessed July 7, 2026. https://rayyanjurnal.com/index.php/qistina/article/view/2427.