Volume 14, Issue 1 Ameur Seddik Closed operator inequalities and open problems Downloads Abstract PDF Full article PDF DOI { copied = true; setTimeout(() => copied = false, 2000) })" :aria-label="copied ? 'DOI copied' : 'Copy DOI'" :title="copied ? 'Copied' : 'Copy DOI'" > Find all available articles from these authors Ameur Seddik Find more articles with the same keywords invertible operator normal operator unitary operator self-adjoint operator unitary reflection operator operator inequality Find more articles with the same subject classes 47B47