%&LaTeX
\documentclass{article}

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

\begin{document}

\begin{thebibliography}{1}

\bibitem{Colomer_etal2003} {\textquotedblleft}\textit{Rings of double-walled carbon nanotube bundles}{\textquotedblright}. Colomer J-F, Henrard L, Flahaut E, Van Tendeloo G, Lucas AA, Lambin P, Nano letters \textbf{3}, 685 (2003).   http://doi.org/10.1021/nl034159w

\end{thebibliography}

\end{document}

