\begin{table}%t1
\caption{Sources of spectroscopic observations.}\label{tab1}
%\centering
\par
\begin{tabular}{llll}
\hline
\hline
Source& Code& Tel. and equip.& Aperture\\
\hline
1&2& 3 &4\\
\hline
SAO (Russia)&    L1&  1 m+UAGS &   $4.2''$ $\times$ $ 19.8''$\\
SAO (Russia)&    L1&  1 m+UAGS &   $8.0''$ $\times$ $ 19.8''$\\
SAO (Russia)&    L &  6 m+UAGS &   $2.0''$ $\times$ $ 6.0''$\\
Guillermo Haro &  GH&  2.1 m+B and C&   $2.5''$ $\times$ $ 6.0''$\\
Obs. (Mexico)    &       &         &             \\
\hline
\end{tabular}
\end{table}