Curvature and Differentiable Structure on Spheres Ernst A. Ruh — 1971 Commentarii mathematici Helvetici
Vanishing Theorems and Almost Symmetrie Spaces of Non-Compact Type. Ernst A. Ruh; Min-Oo — 1981 Mathematische Annalen
Comparison theorems for compact symmetric spaces Min-Oo; Ernst A. Ruh — 1979 Annales scientifiques de l'École Normale Supérieure
Jacobi Fields and Finsler Metrics on Compact Lie Groups with an Application to Differentiable Pinching Problems. Ernst A. Ruh; Karsten Grove; Hermann Karcher — 1974 Mathematische Annalen
An Equivariant Pniching Theorem. Ernst A. Ruh; Hans-Christoph Im Hof — 1975 Commentarii mathematici Helvetici