\begin{table}%T2
\caption{Distances and flux scaling.}
\label{distances}
%\centerline
 {
\begin{tabular}{l l l l}
\hline\hline
Galaxy 		& $d$ (Mpc)& Reference 		      & Factor$^{a}$     \\	
\hline						                             
NGC 4526	& 13	 & \citet{ngc4526}          & $1.5 \times 10^{-5}$ \\
NGC 6181	& 34	 & \citet{silchenko97}      & $1.1 \times 10^{-4}$ \\
\hline
\end{tabular}}
\smallskip
$^a$ Factor used to scale down the flux, computed as \\
~~$~~(d/d_{{\rm L,}z=0.5})^2 \times (1+z)^{-1}$. 
\end{table}