Based on the answer by @raniere-silva, and information on the Creative Commons page, I manage to put the information in a way I liked.
I went to the CC page and download the logo (in svn), based in the kind of license I choose. Using InkScape
I transformed into pdf.
\documentclass{book}
\usepackage{xcolor}
\usepackage[framemethod=tikz]{mdframed}
\definecolor{cccolor}{rgb}{.67,.7,.67}
\begin{document}
\begin{mdframed}[outerlinecolor=black,outerlinewidth=2pt,linecolor=cccolor,middlelinewidth=3pt,roundcorner=10pt]
This work is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.
\begin{center}
\includegraphics[scale=2]{by-nc-sa.pdf}
\end{center}
\end{mdframed}
\end{document}
The final result was