LE DUC ANH; DOAN THI HAI QUYNH; NGO THI HA TRANG. STRONG-COUPLING PERTURBATION THEORY IN A SIMPLE AND EXACTLY SOLVABLE MODEL. HNUE Journal of Science: Journal of Natural Sciences, [S. l.], v. 70, n. 1, p. 36–43, 2025. DOI: 10.18173/2354-1059.2025-0005. Disponível em: https://hnuejs.edu.vn/ns/article/view/615. Acesso em: 18 jul. 2026.