\begin{table}%t9 \caption{\label{table9}Ionic abundance ratios from permitted lines in PB~8$^{a}$.} \small%\centerline { \begin{tabular}{cccc} \hline\hline\noalign{\smallskip} & & \mc{2}{c}{O$^{++}$/H$^+$} \\ \hline\noalign{\smallskip} & & $I$($\lambda$)/$I$(H$\beta$) & X$^{+i}$/H$^+$ \\ Mult. & $\lambda_0$ & ($\times$10$^{-2}$) & ($\times$10$^{-5}$) \\ \hline\noalign{\smallskip} 1$^{b}$& 4638.85 & 0.040~$\pm$~0.010 & 122 \\ & 4641.81 & 0.380~$\pm$~0.030 & 153 \\ & 4649.14 & 0.458~$\pm$~0.037 & 148 \\ & 4650.84 & 0.221~$\pm$~0.027 & 125 \\ & 4661.64 & 0.222~$\pm$~0.027 & 116 \\ & 4673.73 & 0.037: & 113: \\ & 4676.24 & 0.184~$\pm$~0.024 & 210 \\ & Sum & & {\bf 141} \\ 2& 4317.14$^{c}$ & 0.210~$\pm$~0.027 & -- \\ & 4319.63 & 0.081~$\pm$~0.021 & 112 \\ & 4325.76 & 0.036: & 261: \\ & 4336.83 & 0.054~$\pm$~0.019 & 183 \\ & 4345.56$^{c}$ & 0.257~$\pm$~0.028 & -- \\ & 4349.43 & 0.197~$\pm$~0.026 & 100 \\ & 4366.89 & 0.199~$\pm$~0.026 & 260 \\ & Sum & & {\bf 141} \\ 10$^{d}$& 4069.62 & 0.391~$\pm$~0.035 & 158 \\ & 4069.89 & * & * \\ & 4072.15 & 0.265~$\pm$~0.029 & 109 \\ & 4075.86 & 0.275~$\pm$~0.030 & 79 \\ & 4085.11 & 0.086~$\pm$~0.022 & 191 \\ & 4092.93 & 0.038: & 114: \\ & Sum & & {\bf 113} \\ 20$^{d}$& 4097.22$^{c}$ & 0.281~$\pm$~0.031 & -- \\ & 4110.79 & 0.147~$\pm$~0.025 & 601 \\ & 4119.22 & 0.087~$\pm$~0.022 & 97 \\ & Sum & & {\bf 204} \\ 3d--4f$^{d}$&4089.29 & 0.102~$\pm$~0.022 & 85 \\ &4303.82$^{e}$ & 0.086~$\pm$~0.022 & 174 \\ &4609.44 & 0.033: & 64: \\ & Average & & {\bf 85} \\ \hline & Adopted & &{\bf 141~$\pm$~7} \\ \hline\noalign{\smallskip} & & \mc{2}{c}{C$^{++}$/H$^+$} \\ \hline\ 6& 4267.26 & 0.781~$\pm$~0.055 & {\bf 69} \\ & Adopted & &{\bf 69~$\pm$~5} \\ \hline\noalign{\smallskip} & & \mc{2}{c}{N$^{++}$/H$^+$} \\ \hline 48& 4239.40 & 0.128~$\pm$~0.040 & {\bf 30} \\ & Adopted & &{\bf 30~$\pm$~6}\\ \hline\noalign{\smallskip} & & \mc{2}{c}{Ne$^{++}$/H$^+$} \\ \hline 57& 4391.94 & 0.062~$\pm$~0.020 & 15 \\ & 4409.30 & 0.061~$\pm$~0.020 & 24 \\ & Sum & & {\bf 19} \\ & Adopted & &{\bf 19~$\pm$~6 } \\ \hline \end{tabular}} \smallskip $^{a}$ Only lines with intensity uncertainties lower than 40\% have been considered (see text).\\ $^{b}$ Corrected from NLTE effects (see text).\\ $^{c}$ Blended with another line or affected by internal reflections or charge transfer in the CCD.\\ $^{d}$ Recombination coefficients for intermediate coupling \citep{liuetal95}.\\ $^{e}$ Blended with {\oii}~$\lambda$4303.61 line. \end{table}