2-D Radiation Transfer Model of Non-Spherically Symmetric Dust Shell in   P roto-Planetary Nebulae
  We have fitted the HST images and the spectral energy distributions (SEDs) of three proto-planetary nebulae (PPN) with a 2-D radiation transfer model. The geometric and mass loss properties of these PPN are also derived. 
K. Y. L. Su, K. Volk and S. Kwok (University of Calgary)