Damseh, R. A. A., et al. “Transient Mixed Convection Flow of A Second-Grade Visco-Elastic Fluid over a Vertical Surface”. Nonlinear Analysis: Modelling and Control, vol. 13, no. 2, Apr. 2008, pp. 169-7, https://doi.org/10.15388/NA.2008.13.2.14577.