Mathematical Inequalities & Applications · Volume 15, Issue 2 Neumann eigenvalue sums on triangles are (mostly) minimal for equilaterals 15-32 Pages 381-394 DOI 10.7153/mia-15-32 Downloads Short PDF Full PDF PNG Authors R. S. Laugesen Z. C. Pan S. S. Son Keywords isodiametric isoperimetric free membrane Subject classes 35P15 35J20