Senamaw Mequanent Zgeye. 2023. “A COMPARATIVE STUDY ON THE COHERENCE AND DIRECTIONALITY OF HELIUM-NEON AND SEMICONDUCTOR LASERS”. Advanced International Journal of Material Science and Engineering (AIJMSE) 1 (1):68-83. https://zapjournals.com/Journals/index.php/aijmse/article/view/251.