Drupal-Biblio17<style face="normal" font="default" size="100%">Let B(H) denote the C&lowast; -algebra of all bounded linear operators on a complex separable Hilbert space H , and let |||&middot;||| be a unitarily invariant norm on some ideal I of B(H). In this paper, we shall show that: for f, g be two continuous non</style>