%&LaTeX
\documentclass{article}

\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{textcomp}

\begin{document}

\begin{thebibliography}{15}

\bibitem{2421} Miquel Ferrer, I. Bardaji, Ernest Valveny, Dimosthenis Karatzas, \& Horst Bunke. (2013). Median Graph Computation by Means of Graph Embedding into Vector Spaces. In Yun Fu, \& Yungian Ma (Eds.), \textit{Graph Embedding for Pattern Analysis} (pp. 45--72). Springer New York.

\end{thebibliography}

\end{document}

