\begin{table}%T3
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%\centering
\par
\caption{Main properties of the dm radio spikes with and without
internal structure, shorter than 100~ms, observed between February
2000 and December 2001 with the 15-m radio telescope and fast
radiospectrograph of Toru\'n Observatory.}\label{t3}
\begin{tabular}{lrr}
\hline \hline
& {Spikes without internal structure} & %\vline 
{Spikes with internal structure} \\
\hline 
\par
No. spikes & 1699 & 1837 \\
Duration (s) &&\\
min/max & 0.008/0.099 & 0.003/0.099 \\
mean/median (skew.)  & 0.029/0.024 (1.9) & 0.046/0.047 (0.1) \\
Width (MHz): &&\\
min/max & 3.1/31.4 & 3.0/25.9 \\
mean/median (skew.)  & 10.38/9.5 (1.0) & 9.2/8.7 (0.9) \\
Relative width (\%) &&\\
min/max & 0.21/2.24 & 0.21/1.82 \\
mean/median (skew.)  & 0.73/0.68 (1.0) & 0.65/0.61 (0.9) \\
Negative drifts (MHz/s) &&\\
No. spikes   & 381 & 1462 \\
min/max & 64/5462 &63/12141 \\
mean/median (skew.) & 1089/762 (1.7) & 467/321 (9.1) \\
Positive drifts (MHz/s) && \\
No. spikes & 236 & 136 \\
min/max & 111/9102 & 51/13425 \\
mean/median (skew.) & 1460/1113 (2.3) &942/604 (6.1) \\
\hline
\end{tabular}
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\end{table}