\begin{table}%t3
%\centering
\par
\caption{\label{ratios}CO line ratios, computed with the approximation of unresolved sources. In the case of He~2--10 and NGC~5253 the ratios were computed using two different CO(1--0) observations reported in the literature.}
\small\begin{tabular}{lll}
\hline\hline
Source           &   CO(3--2)/CO(1--0)    &   CO(3--2)/CO(2--1)     \\
\hline
He~2--10 (0, 0) &	   0.36    &   0.74      \\
                        &    0.39    &   0.71      \\
NGC~4123     &    0.52    &    0.62    \\	              
NGC~4309     &       --        &      --         \\
NGC~4385     &    0.37    &       --        \\
		      &    0.66    &       --        \\
NGC~4630     &    0.35    &    1.35    \\
NGC~4701     &    0.82    &    2.87    \\
NGC~4713     &    0.22    &       --        \\
NGC~5253     &    0.46    &       --        \\
                        &    0.39    &       --         \\
%                        &1.86$^a$&      --         \\                        
\hline
\end{tabular}
\end{table}