Big Decorative Quotes

I want to make some definition in my thesis very clear, by putting it in its own line, with stylish, decorative (or whatever you call it) quotes. How can I do that in Latex?

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Consider to put your definition into a theorem-like environment. Here's an example using the thmtools package (with ntheorem as backend):

\documentclass{article}

\usepackage{ntheorem}
\usepackage{thmtools}
\declaretheorem[style=mystyle]{definition}

\usepackage[english]{babel}
\usepackage{blindtext}

\begin{document}

\section{foo}

\blindtext

\begin{definition}
\blindtext
\end{definition}

\blindtext

\end{document}

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Sorry for being late, I got busy with other stuff. I am trying this, but I am getting this error on the link containing the definetheoremstyle' command: Undefined control sequence! Any idea how to solve this issue? – Rafid May 20 '11 at 15:58
The command name is \declaretheoremstyle`. – lockstep May 20 '11 at 16:39
Yeah, sorry, that's how I wrote it in the code but it was a mistake in my comment. Any idea why could this be caused?! – Rafid May 20 '11 at 17:11
Does my example compile for you as-is? If not, try to update your TeX distribution. – lockstep May 20 '11 at 17:28
Just tried it. Nope, it doesn't! Just in case you are wondering, I do have the full latex installed on an Ubuntu system, so I don't think it is a package problem (although I believe LaTeX should have mentioned this if it is a package problem). – Rafid May 20 '11 at 17:45