network-spec: fixed a misspelled command

docs/network-spec/miniprotocols.tex

@@ -518,7 +518,7 @@ \subsection{Client and Server Implementation}
       \item if either of them accepts a version by returning \texttt{Accept},
         the other one must accept the same value, i.e. in this case
         \texttt{acceptable proposed received == acceptable received proposed}
-      \item if either of them refuses to accept (returns \textt{Refuse reason})
+      \item if either of them refuses to accept (returns \texttt{Refuse reason})
         the other one shall return \texttt{Refuse} as well.
     \end{itemize}
 \end{description}