Y. Aldouri M, Mahdi DM, M. Saeed DA. EDFA Gain Evaluation in WDM Transmitting System of the Free Space Optics FSO. ASRJETS-Journal. 2019;54(1):122-130. Accessed September 14, 2025. https://www.asrjetsjournal.org/American_Scientific_Journal/article/view/4658