\begin{table}%t2
\caption{\label{dist_com}Distances to the clouds L1517, Cha I, Lup 3 and NGC 7023 compiled from the literature.}
\par
%\centerline
{
\begin{tabular}{l l l l}
\hline\hline
Cloud&Distances quoted&Associated&Ref. 	  \\
Identification&in the literature (pc)&star&\\
\hline
L 1517&$\rm 144^{+23}_{-17}$$^{\dag}$&AB Aur&1\\
Chamaeleon 1&115--215, 158&HD 97048&         2, 3    \\
&$150\pm15$, $\rm 175^{+27}_{-20}$&&4, 1   	     \\
Lupus 3&130--170, 140&HR 5999&5, 6, 7 	\\
&100, $\rm 208^{+46}_{-32}$, $140\pm2$&&8, 9, 10     \\
NGC 7023&440, $\rm 429^{+159}_{-90}$, $288\pm25$&HD 200775&11, 1\\
&$288\pm25$&&12\\
\hline
\end{tabular}}
\par
\medskip 
1-Bertout et~al. (\cite{Bertout99}); 2-Schwartz (\cite{Schwartz91}); 3-Franco (\cite{Franco91}); 4-Whittet et~al. (\cite{Whittet97});
5-Murphy et~al. (\cite{Murphy86}); 6-Krautter (1991); 7-Hughes et~al. (\cite{Hughes93}); 8-Knude \& H{\o}g (\cite{Knude98});
9-van den Ancker et~al. (\cite{Ancker98}); \mbox{10-de~Zeeuw} et~al. (\cite{Zeeuw99}); 11-Viotti (\cite{Viotti69}); 12-Strai\v{z}ys et~al. (\cite{Straizys92}).\\
$^{\dag}$The Hipparcos distance to the AB Aur.
\end{table}