Comments on "A new solution approach for simultaneous heat and mass transfer during convective drying of mango" by E. Barati, JA Esfahani, Journal of Food Engineering 102 (2011) 302-309; "A novel approach to evaluate the temperature during drying of food products with negligible external resistance to mass transfer" by E. Barati, JA Esfahani, Journal of Food Engineering 114 (2013) 39-46