%&LaTeX
\documentclass{article}

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

\begin{document}

\begin{thebibliography}{1}

\bibitem{Wu_etal2010} {\textquotedblleft}\textit{Quantum tunneling through graphene nanorings}{\textquotedblright}. Wu Z, Zhang ZZ, Chang K, Peeters FM, Nanotechnology \textbf{21}, 185201 (2010).   http://doi.org/10.1088/0957-4484/21/18/185201

\end{thebibliography}

\end{document}

