\begin{table}%t7
\caption{Isotopic ratios (with PEs) in 23 red giant stars.\label{tab7}}
%\centerline
 {\begin{tabular}{ r c c  l l }
\hline \hline
\noalign{\smallskip}
   Obj. &  $N_{\rm wk}$(13)$^a$  &  $N_{\rm wk}$(17)$^b$ 
&  $^{12}$C/$^{13}$C  & $^{16}$O/$^{17}$O  \\ 
\noalign{\smallskip}
\hline
\noalign{\smallskip}
$\alpha$ Tau & 2  & 0 &   10.6 $\pm$ 1.0  &  $>$1000    \\
$\delta$ Oph & 3  & 2 &   11.1 $\pm$ 0.9 & ~~~387 $\pm$ 68   \\
$\nu$  Vir   & 5  & 0 &   ~8.7 $\pm$ 1.3 &   $>$2000          \\
$\alpha$ Cet & 2  & 2 &   11.1 $\pm$ 0.8 &   ~~~586 $\pm$ 47  \\
$\sigma$ Lib & 2  & 0 &   ~7.5 $\pm$ 0.3 &   $>$1500  \\
%\noalign{\smallskip}
$\lambda$ Aqr & 2 & 0 &  ~7.9 $\pm$ 1.4 &   $>$1000   \\
$\beta$ Peg  &  3 & 0 &  ~7.7 $\pm$ 0.5 &   $>$2500   \\
$\tau^4$ Eri &  1 & 1 &    12.4 $\pm$ 0.3 &   ~~~687 $\pm$ 14   \\
$\mu$ Gem    & 6  & 1 &  10.5 $\pm$ 1.2  &   ~~~798 $\pm$ 73   \\
$\delta$ Vir & 4  & 0 &  12.3 $\pm$ 1.2 &  $>$2500   \\
%\noalign{\smallskip}
10 Dra       & 3  & 3 &  14.8 $\pm$ 1.6 &  ~~~151 $\pm$ 11   \\
$\rho$ Per   & 2  & 0  &  ~9.7 $\pm$ 1.0 &  $>$1000  \\
BS6861       & 1  & 0  &  48.5 $\pm$ 2.9 &  $>$1000   \\
$\delta^2$ Lyr & 2 & 2 & 16.2 $\pm$ 1.5 & ~~~465 $\pm$ 41  \\
RR UMi       & 1  & 0  &10.0 $\pm$  0.8 &  $>$2000    \\
%\noalign{\smallskip}
$\alpha$ Her & 2 & 4 & 11.1 $\pm$ 0.7 & ~~~102 $\pm$ ~8  \\
OP Her       & 2 & 1 & 11.3 $\pm$ 1.2 & ~~~329 $\pm$ 31  \\
XY Lyr       & 1 & 3 &  15.0 $\pm$ 0.4 & ~~~223 $\pm$ 16    \\
R Lyr        & 1 & 3 &~6.4 $\pm$ 0.3 & ~~~368 $\pm$ 44   \\
RZ Ari       & 3 & 2 &~7.9 $\pm$ 0.8 & ~~~607 $\pm$  48  \\
%\noalign{\smallskip}
30g Her      & 2 & 3 & 12.5 $\pm$ 1.1 & ~~~211 $\pm$ 42   \\
SW Vir       & 2 & 2 & 22.0 $\pm$ 4.7 & ~~~432 $\pm$ 37  \\
RX Boo       & 0 & 3 &    ~~~...       & ~~~233 $\pm$  20  \\
\noalign{\smallskip}
\hline 
\end{tabular}}
\par
\smallskip
\par
$^{{a}}$   Number of weak lines of 
$^{13}$C$^{16}$O; 
$^{{b}}$   number of weak lines of 
$^{12}$C$^{17}$O. 
\end{table}