Ammar, A., F. Z. Boutaf, and A. Jeribi. “Essential Spectra in Non-Archimedean Fields”.
Matematychni Studii
58, no. 1 (October 31, 2022): 82-93. Accessed April 9, 2025. http://matstud.org.ua/ojs/index.php/matstud/article/view/293.