arXiv · 0801.1923
The aim of this paper is to classify bi-Hermitian compact surfaces $(M,g)$ whose Ricci tensor $\rho$ satisfies the relation $\nabla_X\rho(X,X) =\frac13X\tau g(X,X)$.
Wlodzimierz Jelonek. 2008-01-12. Bi-Hermitian gray surfaces II. https://arxiv.org/abs/0801.1923
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