\begin{table}%t3
\caption {\label{gasdata}The calculated temperatures and column densities.} 
\small%\centerline
 {
\begin{tabular}{l c c c c }         
\hline\hline                  
Source&Molecule&Line width&$T_{\rm rot}$&$N_{\rm X}$\\     
&&(km s$^{-1}$)&(K)&($\times10^{13}$ cm$^{-2}$)\\
\hline      
IRAS 03254&CH$_3$OH&0.42--0.49&6 $\pm$ 2&1.8 $\pm$ 1.8\\
&HNCO&0.77&$\sim$4&$\sim$0.48\\
B1-b&CH$_3$OH&0.77--0.88&7 $\pm$ 1&25 $\pm$ 13\\
&HNCO&0.86&$\sim$7&$\sim$2.4\\
L1489 IRS&CH$_3$OH&0.75--0.97&6 $\pm$ 2&1.8 $\pm$ 1.3\\
&HNCO&--&$\sim$6&$<$0.095\\
SVS 4-5&CH$_3$OH&2.4--4.0&7 $\pm$ 1&27 $\pm$ 10\\
&HNCO&2.6--2.9&9 $\pm$ 6&0.38 $\pm$ 0.38\\
\hline
Elias 29$^{a}$&CH$_3$OH&1.3&$\sim$$9$&$\sim$0.73\\
R CrA 7A$^{b}$&CH$_3$OH&2.4--3.0&18 $\pm$ 2&59 $\pm$ 28\\
R CrA 7B$^{b}$&CH$_3$OH&2.1--2.6&19 $\pm$ 1&94 $\pm$ 28\\
\hline                                    
\end{tabular}}
\medskip
$^{a}$ \citet{Buckle02};
$^{b}$ derived from \citet{Schoier06} using rotational diagrams.
\end{table}