Riemannian manifolds admitting a conformal transformation group.
Let M be a Riemannian manifold with constant scalar curvature K which admits an infinitesimal conformal transformation. A necessary and sufficient condition in order that it be isometric with a sphere is obtained.Inequalities giving upper and lower bounds for K are also derived.
Yano
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DEPARTMENT OF MATHEMATICS, UNIVERSITY OF ILLINOIS, URBANA.