Tuan, Pham Viet, et al. “A Spectral Efficiency Design for Active IRS-Assisted SWIPT System via Semidefinite Relaxation Method”. Journal of Telecommunications and Information Technology, vol. 103, no. 1, Mar. 2026, pp. 40-49, https://doi.org/10.26636/jtit.2026.1.2267.