Nguyễn , N.H.M.T. et al. 2026. EVALUATING SLEEP QUALITY AMONG ELDERLY AT TWO CARDIOLOGY OUTPATIENT CLINICS OF THONG NHAT HOSPITAL, HO CHI MINH CITY. Vietnam Medical Journal. 562, 3 (Aug. 2026). DOI:https://doi.org/10.51298/vmj.v562i3.18469.