\begin{table}%t1
%\centering
\par
\caption{\label{tab1}Summary of published  observations utilised in this study.}
\begin{tabular}{lll}
\hline \hline \noalign{\smallskip}
Year  & Dataset & Reference \\
\hline
1961 &  $VI$ band phot. & Borgman et~al. (\cite{borgman}) \\
1966 &  $VRI$ band phot. & West87 \\
1969    & $K$ band phot. & Borgman et~al. (\cite{borgman}) \\
1973    & $V$+narrow band phot. & Lockwood (\cite{lockwood74}) \\
1973-4   & 2--20~$\mu$m phot. & Koornneef (\cite{koor}) \\
1995    & $VI$ band phot. & Piatti et~al. (\cite{piatti}) \\
 2001   & $BVRI$ band phot. & C05 \\
2006    & $BVRI$ band  phot. & Bonanos (\cite{bonanos}) \\
\hline
1981    & $RI$ band spec. & West87 \\
2001    & $RI$ band spec. & C05 \\
2002    & $RI$ band spec. & C05 \\
2003    & $RI$ band spec. & Negueruela \\
        &               & \& Clark (\cite{nc})\\
2005    & $IJ$ \& $HK$ spec. & Crowther et~al. (\cite{crowther}) \\
2006   & $K$ band spec. & Mengel \& \\
       &              & Tacconi-Garman (\cite{mengel})\\
\hline
\end{tabular}
\end{table}