Update SDDS-XDC.tex

contributions/sdds-xdc/SDDS-XDC.tex

@@ -237,7 +237,7 @@ components whose goal is to maximise the accessibility of data to clients while
  are aggregated globally through a federation.
 To such purpose, various technologies are available to the project to serve as the basis of an implementation:
 \begin{itemize} 
-\item The system runs native dCache \cite{dcache} or EOS, but operates in a "caching mode" staging data in 
+\item The system runs native dCache \cite{dcache} or EOS, but operates in a ``caching mode'' staging data in 
 when a cache miss occurs.
 \item A service such as Dynafed \cite{dynafed} will be augmented to initiate data movement. While it would 
 hold only metadata, it would use a local storage system for this.