Sykopetritou , ​Irene and Xenophontos , Christos. (2021). An $hp$ Finite Element Method for a Singularly Perturbed Reaction-Convection-Diffusion Boundary Value Problem with Two Small Parameters.
            <i>International Journal of Numerical Analysis and Modeling</i>. <i>18</i> (4).
            481-499.
         doi: