\begin{table}%t2
%\centering
\par
\caption{\label{t:comp_feh}Two by two comparison of homogeneous sets of spectroscopic metallicities (see text).}
\begin{tabular}{l l r r r r}
\hline \hline 
Reference 1 & Reference 2 & $\Delta_{\FeH}$ & $\sigma_{\FeH}$ & $N_{\rm c}$  &   $N_{\rm o}$ \\
\hline 
Fuhrmann        & Mishenina       &  0.01 &  0.07 & 137 &   3 \\ 
Fuhrmann        & Valenti         & --0.03 &  0.05 & 179 &   3 \\ 
Gratton         & Mishenina       & --0.02 &  0.10 & 103 &   0 \\ 
Gratton         & Ram{\'{\i}}rez   &  0.02 &  0.08 & 110 &   2 \\ 
Hekker          & McWilliam       &  0.07 &  0.10 & 211 &   5 \\ 
Luck            & Valenti         & --0.01 &  0.06 & 136 &   4 \\ 
Mishenina       & Valenti         & --0.04 &  0.07 & 162 &   4 \\ 
Ram{\'{\i}}rez   & Valenti         & --0.07 &  0.06 & 137 &   3 \\ 
\hline
\end{tabular}
\tablefoot{A simple statistic with  $3\sigma$ rejection has been applied. $N_{\rm c}$ is the number of common stars, $N_{\rm o}$ is the number of $3\sigma$ outliers.}
\end{table}