Le Duc Anh, Doan Thi Hai Quynh, and Ngo Thi Ha Trang. “STRONG-COUPLING PERTURBATION THEORY IN A SIMPLE AND EXACTLY SOLVABLE MODEL”. Journal of Science Natural Science 70, no. 1 (March 31, 2025): 36–43. Accessed December 5, 2025. https://hnuejs.edu.vn/ns/article/view/615.