  In this article we study the spherical mean Radon transform in $\mathbf R^3$
with detectors centered on a plane. We use the consistency method suggested by
the author of this article for the inversion of the transform in 3D. A new
iterative inversion formula is presented. This formula has the benefit of being
local and is suitable for practical reconstructions. The inversion of the
spherical mean Radon transform is required in mathematical models in thermo-
and photo-acoustic tomography, radar imaging, and others.
