Three-Dimensional Riemannian Manifolds Associated with Locally Conformal Riemannian Product Manifolds

A 3-dimensional Riemannian manifold (M, g, Q) with a tensor structure Q whose fourth power is the identity is associated with a Riemannian almost product manifold (M, g, P), where P = Q^2. The almost product manifold (M, g, P) is shown to belong to the class of locally conformal Riemannian product manifolds.