Tench, Robert E. “Design of a Novel 31.5 THz Bandwidth Hybrid TDFA-HDFA at 2000 Nm and Its Applications in Unregenerated DWDM Lightwave Transmission Systems”. Journal of Optics and Photonics Research 2, no. 2 (December 31, 2024): 55–66. Accessed June 7, 2025. https://ojs.bonviewpress.com/index.php/JOPR/article/view/4305.