  The first goal of this note is to study the Almansi property on an
m-dimensional model in the sense of Greene and Wu and, more generally, in a
Riemannian geometric setting. In particular, we shall prove that the only model
on which the Almansi property is verified is the Euclidean space R^m. In the
second part of the paper we shall study Almansi's property and biharmonicity
for functions which depend on the distance from a given submanifold. Finally,
in the last section we provide an extension to the semi-Euclidean case R^{p,q}
which includes the proof of the classical Almansi property in R^m as a special
instance.
