\begin{table}%t3
\par
\caption{\label{tab:ratio}CN number ratios.}
%\centerline
 {\begin{tabular}[l]{p{2.65cm} p{0.75cm} p{1.7cm} p{2.2cm}}
\hline\hline
\noalign{\smallskip}
Cluster & $\frac{\rm CN_{weak}}{\rm CN_{strong}}$ & $r_{\rm lower RGB}$ & $r_{\rm upper RGB}$ \\
\hline
NGC~288          & 9/7  & $0.78\pm0.39$ &          \\	
NGC~362          & 9/11 & $1.22\pm0.55$ & 2.46$^a$ \\
NGC~5286         & 2/4  & $2.00\pm1.73$ &	    \\
NGC~6656 (M~22) & 10/6 & $0.60\pm0.31$ & 0.41$^b$ \\
Ter~7	          & 14/0 & $0.00\pm0.00$ &          \\
NGC~6809 (M~55) & 13/2 & $0.15\pm0.12$ & 0.22$^c$ \\
NGC~7078 (M~15) & 18/1 & $0.06\pm0.06$ &          \\
                  & (12/7) & ($0.60\pm0.29$) &      \\
Pal~12           & 13/1 & $0.07\pm0.07$ &          \\
\hline
NGC~104 (47~Tuc)&      & $1.90^d$      & 1.8$^d$  \\
NGC~6839 (M~71) & 13/9 & $0.69^e$      & 1.0$^e$, 0.63$^g$, 0.3$^h$\\
\hline
NGC~1904 (M~79) &      &               & 2.6$^b$ \\
NGC~2808         &      &               & 2.4$^f$ \\
NGC~3201         &      &               & 1.1$^f$ \\
NGC~5272 (M~3)  &      &               & 0.6$^f$ \\
NGC~5904 (M~5)  &      &               & 3.0$^f$ \\
NGC~6121 (M~4)  &      &               & 1.4$^f$ \\
NGC~6171 (M~107)&      &               & 1.4$^f$ \\
NGC~6205 (M~13) &      &               & 3.2$^f$ \\
NGC~6254 (M~10) &      &               & 0.5$^f$ \\
NGC~6637         &      &               & 1.2$^f$ \\
NGC~6752         &      &               & 1.6$^f$ \\
NGC~6934         &      &               & 0.6$^f$ \\
NGC~7006         &      &               & 2-3.5$^b$ \\
NGC~7089 (M~2)  &      &               & 3.8$^f$ \\
\hline 
\end{tabular}}
\par
\smallskip
{$^a$~\citet{S/M:90}; $^b$~\citet{H/S/G:03b}; $^c$~\citet{N:87}; $^d$~\citet{B:97}; $^e$~\citet{L:05};
$^f$~\cite{S:02}; $^g$~\cite{C:99.2}; $^h$~\cite{P:92}.}
\end{table}