diff --git a/doc/glm.tex b/doc/glm.tex
index f77dac00..c37a1cc6 100644
--- a/doc/glm.tex
+++ b/doc/glm.tex
@@ -1282,7 +1282,7 @@ The Doxygen-generated documentation includes a complete list of all extensions,
 
 GLM is designed for convenience over performance.  \emph{That being said}, the most frequently-used operations are optimized to the fullest reasonable extent.  Approximations and SIMD-flavored structures are provided as well, in case they're needed.
 
-\subsection{Visual C++ gives me lots of warnings on on warning level \texttt{/W4}.}
+\subsection{Visual C++ gives me lots of warnings on warning level \texttt{/W4}.}
 
 You should not have any warnings, even in \verb|/W4| mode. However, if you expect such level for your code, then you should ask for the same level to the compiler by at least disabling the Visual C++ language extensions (\verb|/Za|) which generates warnings when used. If these extensions are enabled, then GLM will take advantage of them and the compiler will generate warnings.