“…In particular, the horospherical Radon transform on trees has been studied in [7,12,15,20] and the X-ray transform in [1,6]. Homogeneous trees do not provide a discrete model for n-dimensional hyperbolic space except when n = 2 (that is, for the disc); discrete models for higher dimensional hyperbolic spaces should be obtained from higher-rank Bruhat-Tits buildings, see [3,4].…”