3-Manifolds with Positive Flat Conformal Structure
  In this paper, we consider a closed 3-manifold $M$ with flat conformal structure $C$. We will prove that, if the Yamabe constant of $(M, C)$ is positive, then $(M, C)$ is Kleinian. 
Reiko Aiyama and Kazuo Akutagawa
math.DG math.GT