Volume 17, Issue 1 He-Jun Sun Ling-Zhong Zeng Estimates for lower bounds of eigenvalues of the Klein-Gordon operator 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 He-Jun Sun Ling-Zhong Zeng Find more articles with the same keywords eigenvalue inequality Klein-Gordon operator Find more articles with the same subject classes 35P15