\begin{table}%t3
\caption{Element abundances.}\label{tab3}
\small%\centerline
{
\begin{tabular}{lcccc} 
\hline \hline
           & \multicolumn{1}{c}{SDSS}&& \multicolumn{2}{c}{3.6 m} \\ \cline{2-2}
\cline{4-5}
Property       &J0113$+$0052$^a$&&J2104$-$0035N&J0113$+$0052 \\ \hline
$T_{\rm e}$(O {\sc iii}), K           &22~520 $\pm$ 7360 &&20~060 $\pm$ 620  &22~880 $\pm$ 2990  \\
$T_{\rm e}$(O {\sc ii}), K            &15~480 $\pm$ 4510 &&15~610 $\pm$ 450  &15~410 $\pm$ 1780  \\
O$^+$/H$^+$, ($\times$10$^5$)     &0.567 $\pm$ 0.421&&0.182 $\pm$ 0.016&0.575 $\pm$ 0.179 \\
O$^{2+}$/H$^+$, ($\times$10$^5$)  &0.836 $\pm$ 0.593&&1.630 $\pm$ 0.116&0.906 $\pm$ 0.256 \\
O/H, ($\times$10$^5$)             &1.403 $\pm$ 0.727&&1.812 $\pm$ 0.117&1.481 $\pm$ 0.313 \\
12 + log O/H                        &7.15 $\pm$ 0.23  &&7.26 $\pm$ 0.03  &7.17 $\pm$ 0.09   \\ 
N$^+$/H$^+$, ($\times$10$^7$)     &2.479 $\pm$ 2.041&&     ...       &      ...       \\
$ICF$(N)                          &      2.49     &&     ...       &      ...       \\
N/H, ($\times$10$^7$)             &5.662 $\pm$ 5.049&&     ...       &      ...       \\
log N/O                           &--1.39 $\pm$ 0.45&&     ...       &      ...       \\ 
Ne$^{2+}$/H$^+$, ($\times$10$^6$) &2.542 $\pm$ 1.649&&2.794 $\pm$ 0.211&2.624 $\pm$ 0.771 \\
$ICF$(Ne)                         &      1.17     &&     1.04      &     1.17       \\
Ne/H, ($\times$10$^6$)            &2.981 $\pm$ 2.768&&2.914 $\pm$ 0.235&3.058 $\pm$ 1.260 \\
log Ne/O                          &--0.67 $\pm$ 0.46&&--0.79 $\pm$ 0.05&--0.69 $\pm$ 0.20 \\
\hline
\end{tabular}}
\medskip
$^a$ O$^+$/H$^+$ is obtained adopting the [O {\sc ii}] $\lambda$3727 emission
line flux from the 3.6 m observations.
\end{table}