“…families of different metrics having the same un-parametrized geodesics) have been studied intensively by Matveev, Bolsinov, Topalov [4,20] and other authors. In particular, they showed that these metrics are integrable, can be quantized into integrable SDS of type (p, 0, 0) in our sense, and are essentially the same as the so called (separable Stäckel-) Benenti systems studied by Benenti and many other authors in classical and quantum mechanics, see, e.g., [2,4,6,20]. The metrics (induced from R n ) on multi-dimensional ellipsoids belong to this family of integrable metrics, and so the Brownian motion on a p-dimensional ellipsoid is an integrable SDS of type (p, 0, 0).…”