  Particle transport through a duct by Lambertian reflection from duct walls is
again considered. This popular transport example has been solved by most
numerical transport methods except notably one- the method of doubling. We
shall show that the method of doubling provides every bit as, or more, accurate
reflectances and transmittances as the numerical discrete ordinates (NDO) and
analytical discrete ordinates (ADO) methods with less mathematical and
numerical effort.
