RUGIRI, Peter Githara. Characterisation of weyl spectrum in Hilbert spaces. Journal of Physical and Applied Sciences (JPAS), [S. l.], v. 2, n. 1, p. 65–72, 2023. DOI: 10.51317/jpas.v2i1.400. Disponível em: https://journals.editononline.com/index.php/jpas/article/view/400. Acesso em: 25 may. 2026.