How can I reverse some arrows of the diagram given by the code below?
\begin{tikzpicture}
% Tell it where the nodes are
\node (A) {$A$};
\node (B) [below=of A] {$B$};
\node (C) [right=of A] {$C$};
\node (D) [right=of B] {$D$};
% Tell it what arrows to draw
\draw[-stealth] (A)-- node[left] {\small $i$} (B);
\draw[-stealth] (B)-- node [below] {\small $g$} (D);
\draw[-stealth] (A)-- node [above] {\small $j$} (C);
\draw[-stealth] (C)-- node [right] {\small $k$} (D);
\end{tikzpicture}
