Tajmouati, A., Boua, H. and Karmouni, M. (2016) “QUASI-FREDHOLM, SAPHAR SPECTRA FOR \(C_{0}\) SEMIGROUPS GENERATORS”, Italian Journal of Pure and Applied Mathematics, 36, pp. 359–366. Available at: https://journals.uniurb.it/index.php/ijpam/article/view/6619 (Accessed: 5 September 2026).