G. Catino:
Generalized quasi-Einstein manifolds with harmonic Weyl tensor
(preprint) 2010

G. Catino, C. Mantegazza, L. Mazzieri, M. Rimoldi:
Locally conformally flat quasi-Einstein manifolds
(preprint) 2010

G. Moreno:
The Bianchi variety
(preprint) 2010