  We consider an inverse source problem in the stationary radiative transport
through an absorbing and scattering medium in two dimensions. Using the
angularly resolved radiation measured on an arc of the boundary, we propose a
numerical algorithm to recover the source in the convex hull of this arc. The
method involves an unstable step of inverting a bounded operator whose range is
not closed. We show that the continuity constant of the discretized inverse
grows at most linearly with the discretization step, thus stabilizing the
problem.
