Sankar, M., and M. Venkatachalappa. “Numerical Investigation of Combined Buoyancy and Surface Tension Driven Convection in an Axi-Symmetric Cylindrical Annulus”. Nonlinear Analysis: Modelling and Control, vol. 12, no. 4, Oct. 2007, pp. 541-52, https://doi.org/10.15388/NA.2007.12.4.14685.