Conformal Vector Fields and Eigenvectors of Laplacian Operator

Certain conditions for a Riemannian manifold to be isometric with a sphere

Morio Obata · Journal of the Mathematical Society of Japan · 1962 · 689 citations · Full text

Certain Conditions, Global Geometry, Geometry +4

Complete Riemannian manifolds and some vector fields

Yoshihiro Tashiro · Transactions of the American Mathematical Society · 1965 · 296 citations

Global Geometry, Geometry, Riemannian Geometry +2

Conformal transformations of Riemannian manifolds

Morio Obata · Journal of Differential Geometry · 1970 · 98 citations · Full text

Geometry, Riemannian Geometry, Conformal Transformations +2

Some differential equations on Riemannian manifolds

Shûkichi Tanno · Journal of the Mathematical Society of Japan · 1978 · 82 citations · Full text

On a Differential Equation Characterizing a Riemannian Structure of a Manifold

Masahiko Kanai · Tokyo Journal of Mathematics · 1983 · 64 citations · Full text