\begin{table}%t2
%\centering
\par
\caption{List of the {\it XMM-Newton} observations. Column (1): Name of the source; 
 Col.~(2): observation date (dd/mm/yyyy),  Col.~(3): orbit revolution number, 
 Col.~(4): Observation ID, and Col.~(5): data exposure time of the pn data (in ks), 
 except for PG~0804+761 for which the MOS exposure time is given.\label{tab:obs}}
\begin{tabular}{llllr}
\hline
\hline
\noalign {\smallskip} 
Source               &   \multicolumn{1}{c}{Obs. Date} &  \multicolumn{1}{c}{Rev.} & \multicolumn{1}{c}{Obs-ID}     &\multicolumn{1}{c} {Exp. }  \\
%                         &                     &                      &                & \multicolumn{1}{c} {(ks)}  \\
\noalign {\smallskip} 
\hline
%\hline
\noalign {\smallskip} 
I~Zw1 &    22/06/2002  & 464    &  0110890301  & 18.7\\
%\noalign {\smallskip} 
PG~0804+761 &    04/04/2000  &  166&0102040401 & 6.7\\
%\noalign {\smallskip}               
 PG~0947+396  &   03/11/2001& 349&0111290101 &17.6 \\ 
%\noalign {\smallskip}                       
PG~0953+414  &    22/11/2001& 358&0111290201&11.5 \\
%\noalign {\smallskip}    
PG~1048+342  &    13/05/2002 &444&0109080701 & 28.1  \\ 
%\noalign {\smallskip}                       
PG~1114+445  &  14/05/2002  & 445& 0109080801& 35.0 \\
%\noalign {\smallskip}                       
PG~1115+407 &  02/12/2001 &446& 0111290301 & 15.0  \\ 
%\noalign {\smallskip}                       
PG~1116+215  & 02/12/2001 & 363& 0111290401& 5.5  \\
%\noalign {\smallskip}                       
PG~1202+281  &  30/05/2002 &453& 0109080101&12.0  \\
%\noalign {\smallskip}                       
PG~1244+026  &  17/06/2001 &279& 0051760101&7.2  \\
%\noalign {\smallskip}                       
PG~1307+085  &  13/06/2002   &460& 0110950401 & 11.2  \\ 
%\noalign {\smallskip}                       
PG~1309+355  &  10/06/2002 & 458& 0109080201  & 22.3  \\ 
%\noalign {\smallskip}                       
PG~1322+659  & 11/05/2002 & 443& 0109080301& 8.7  \\ 
%\noalign {\smallskip}                       
PG~1352+183  &  20/07/2002 & 478 & 0109080401 & 12.5\\
%\noalign {\smallskip}                       
PG~1402+261  &   27/02/2002 &391& 0109081001& 9.1  \\
%\noalign {\smallskip}     
Mrk 1383   &  28/07/2000& 116  & 0102040501 & 5.4\\
%\noalign {\smallskip}                       
PG~1427+480  & 31/05/2002 & 453& 0109080901 & 31.2  \\
%\noalign {\smallskip}          
Mrk 478 & 23/12/2001  & 373       & 0107660201  &9.1\\             
%\noalign {\smallskip}          
PG~1512+370   & 25/08/2002 & 496 &   0111291001  &  17.6   \\             
%\noalign {\smallskip}                       
Mrk 876              & 29/08/2001 & 315  &  0102041301  & 2.5 \\
%\noalign {\smallskip}                       
PG~1626+554   & 05/05/2002 &440& 0109081101 & 5.5  \\
\hline
\end{tabular}
\end{table}