\begin{table}%t3
%\centering
\par
\caption{\label{tab:solabb}Initial helium $Y_{\rm ini}$ and metal $Z_{\rm ini}$ abundances provided by  recent standard solar models by different authors (see footnotes).}
\begin{tabular}{cccc}
\hline \hline \noalign{\smallskip}
 Models & $Y_{\rm ini}$ & $Z_{\rm ini}$ & $\Delta Y/ \Delta Z$ \\
\hline\noalign{\smallskip}
 Pisa\tablefootmark{a}  & 0.2532 & 0.0137  &  0.380 \\
 B2005\tablefootmark{b} & 0.2614 & 0.0140  &  0.957 \\
 G2006\tablefootmark{c} & 0.2570 & 0.0135  &  0.666 \\
 S2009\tablefootmark{d} & 0.2593 & 0.0139  &  0.813 \\
 S2009b\tablefootmark{e} & 0.2617 & 0.0149  &  0.919 \\
\hline
\end{tabular}
\tablefoot{Models are computed adopting the heavy element mixture by
\citet{aspl05}.}\vspace{-2mm}
\tablebib{\tablefoottext{a}{\citet{tognelli10},} 
\tablefoottext{b}{\citet{bahcall05},}   
\tablefoottext{c}{\citet{guzik05},} 
\tablefoottext{d}{\citet{serenelli09},} 
\tablefoottext{e}{\citet{serenelli09}, mixture by \citet{aspl09}.}}\vspace{-3mm}
\end{table}