\begin{table}%T1
\caption{Summary of the data used to build the spectral energy distribution  of Q0056-363. 
C03: Cutri et~al. (\cite{Cutri2003}).  
M03: Monet et~al. (\cite{Monet2003}).  
UVW2 is the OM filter used during the present {\it XMM-Newton} observation. 
G99: Grupe et~al. (\cite{Grupe99}).   
INES: Merged Log of {\sl IUE} Observations (NASA-ESA, 1999).
}
\label{table:sed}
%\centering
\par
\begin{tabular}{cccc}
\hline
\hline
\noalign {\smallskip}    
 Filter            &     magnitude or flux                    &  Observation date   &     reference\\
\noalign {\smallskip}        
wavelength or energy   band  &                            &                                &                    \\                 
\noalign {\smallskip}                       
\hline
\noalign {\smallskip}                       
$K_{\rm s}$               & $12.301\pm0.032$~mag  &  07/1999  & C03\\
\noalign {\smallskip}                       
$H$                        &  $13.390\pm0.044$~mag      & 07/1999 & C03\\
\noalign {\smallskip}                       
$J$                         &  $14.228\pm0.037$~mag    &  07/1999 & C03 \\
\noalign {\smallskip}                       
$I$                         &  14.69  mag                              &  02/1987           &  M03 \\
\noalign {\smallskip}                       
[6600--7820~\AA]  (Red) &     (spectrum)                                 &  10/1993          &   G99      \\
\noalign {\smallskip}                       
[4640--5950~\AA]  (Blue) &      (spectrum)                                  &    10/1993       &   G99      \\
\noalign {\smallskip}                       
OM    (UWV2)       &  $2.11\pm0.04$     erg~cm$^{-2}$~s$^{-1}$~A$^{-1}$     &  07/2000               & this work\\
\noalign {\smallskip}                       
 IUE     (UV: [1151--1979~\AA])                    &    (spectrum)               &   10/1995                                 &  INES          \\
\noalign {\smallskip}                       
 XMM (X-rays: 0.3--10~keV)         &    (spectrum)                             &   07/2000              &this work\\
\noalign {\smallskip}                       
\hline
\end{tabular}
\end{table}