\begin{table}%t1
\par
      \caption{\label{INTEGRAL_Periods}Pulse periods of \oao\ as measured during the
      \emph{INTEGRAL} GPS in 11 observation groups. The
      date is the centre of the observation time interval.}
\small
         %\centering
\par
      \begin{tabular}{r l l l l}
      \hline \hline\noalign{\smallskip}
             Grp.     & Date       & Range        & Period       &  $\dot{P}$\\
                      & [MJD]      & [d]          & [s]          &  [$10^{-9}$~s~s$^{-1}$] \\
      \hline
             1        &  52~672.03  & $\pm$0.67    & 37.1467  (1) &                    \\
             2        &  52~711.48  & $\pm$12.87   & 37.1645  (5) &  $2.9\pm1.0$       \\
             3        &  52~859.94  & $\pm$0.18    & 37.2028  (5) &                    \\
             4        &  52~869.95  & $\pm$0.91    & 37.2005  (5) &                    \\
             5        &  52~908.42  & $\pm$0.35    & 37.2008  (5) &                    \\
             6        &  53~054.92  & $\pm$0.07    & 37.2262 (50) &                    \\
             7        &  53~232.53  & $\pm$0.53    & 37.2712  (2) &                    \\
             8        &  53~255.48  & $\pm$0.36    & 37.2819  (3) &                    \\
             9        &  53~464.74  & $\pm$1.63    & 37.2060 (15) &                    \\
             10       &  53~650.10  & $\pm$0.57    & 37.1137  (7) &                    \\
             11       &  53~789.58  & $\pm$5.32    & 37.1209  (6) &                    \\
      \hline
      \end{tabular}
  \end{table}