  We carried out the detailed group classification of the potential in
Klein-Gordon equation in anisotropic Riemannian manifolds. Specifically, we
consider the Klein-Gordon equations for the four-dimensional anisotropic and
homogeneous spacetimes of Bianchi I, Bianchi\ III and Bianchi V. We derive all
the closed-form expressions for the potential function where the equation
admits Lie and Noether symmetries. We apply previous results which connect the
Lie symmetries\ of the differential equation with the collineations of the
Riemannian space which defines the Laplace operator, and we solve the
classification problem in a systematic way.
