ON THE SPACE OF 3--DIMENSIONAL HOMOGENEOUS RIEMANNIAN MANIFOLDS Hans - J\"urgen Schmidt 1991 Math. Subject Classification: 53B20. Key words: Homogeneous Riemannian manifolds, local classification in $d=3$. Abstract: We answer the following question: Let $\lambda$, $\mu$, $\nu$ be arbitrary real numbers. Does there exist a 3--dimensional homogeneous Riemannian manifold whose eigenvalues of the Ricci tensor are just $\lambda$, $\mu$, and $\nu$?