\begin{table}%t2
\par
         \caption {\label{coefceres}Values of $c_{\rm a}$ and $c_{\lambda}$ for the upper limits on the period
	          of~10 and 50~years. } 
\par
%\centerline
 {          \begin{tabular}{c c c c }  
            \hline\hline 
             Filters       & Argument   & Amplitude  &  Period                        \\
	     in period     &            &  $c_{\rm a}$   &   $P_{c_{\rm a}}$ \\ 
                           &            & $\left[\rm AU\right]$ & $\left[\rm years\right]$  \\[-0.25cm] \\
         \hline 
             10 years   &  2$\bar{\lambda}_{\rm M}$  -- 2$\bar{\lambda}_{\rm c}$ & $3.31 \times 10^{-10}$ & 1.6  \\
	     50 years   &  2$\bar{\lambda}_{\rm M}$  -- 5$\bar{\lambda}_{\rm c}$ & $4.05 \times 10^{-10}$ & 45.8  \\ 
            \hline\\[1mm]
         \end{tabular}}
        %\centerline
 {  \begin{tabular}{c c c c c}
            \hline\hline 
             Filters       & Argument   & Amplitude  &  Period                        \\
	     in period     &            &  $c_{\lambda}$   &   $P_{c_{\lambda}}$                 \\ 
                           &            & $\left[\rm radian\right]$ & $\left[\rm years\right]$ \\[-0.25cm] \\
        \hline 
             10 years   &  2$\bar{\lambda}_{\rm M}$ -- 4$\bar{\lambda}_{\rm c}$  & $6.15 \times 10^{-10}$ & 5.1 \\
	     50 years   &  2$\bar{\lambda}_{\rm M}$ -- 5$\bar{\lambda}_{\rm c}$  & $9.28 \times 10^{-9}$  & 45.8 \\ 
            \hline
         \end{tabular}}
\par
         \smallskip
         The arguments 
	          are given as a combination of the  mean   motions of Mars $\bar{\lambda}_{\rm M}$ and of Ceres $\bar{\lambda}_{\rm c}$.	 
\par
   \end{table}