Transport in Porous Media, Vol.54, No.3, 265-271, 2004
The free convection boundary-layer flow induced in a fluid saturated porous medium by a non-isothermal vertical cylinder approaches the shape of Schlichting's round jet as the cylinder radius tends to zero
The title statement is proven for a circular cylinder whose surface temperature ( above that of the ambient fluid) varies inversely proportional with the axial distance from the leading edge.