YANG, Yaqiao. Qinhuangdao City’s Elderly Care Industry Planning Based on the Least Squares Method. Mathematical Modeling and Algorithm Application, [S. l.], v. 4, n. 2, p. 55–60, 2025. DOI: 10.54097/r6kccs26. Disponível em: https://drpress.org/ojs/index.php/mmaa/article/view/30317. Acesso em: 24 aug. 2026.