\begin{table}%T4
\caption{\label{tab:spectra}Seyferts from Table~\ref{tab:seyferts} that have
dual-frequency (18~cm and 6~cm) VLBI observations with matching beam
sizes, from which the spectral index is derived. Asterisks denote
objects with at least one component with a flat or inverted spectrum.}
 %\centering
\par
\begin{tabular}{lclrl}
\hline
\hline\noalign{\smallskip}
\multicolumn{1}{c}{Source} 
& \multicolumn{1}{c}{Flat/Inv.}
& \multicolumn{1}{c}{Comp.}
& \multicolumn{1}{c}{$\alpha^{18}_{6}$}
& \multicolumn{1}{c}{Ref.}
\\
\noalign{\smallskip}\hline\noalign{\smallskip}
\object{Mrk  231}   & * &   N    &   $-$0.86  &   \cite{1999ApJ...516..127U}    \\ 
                    &   &   C    &   $+$0.88  &   \cite{1999ApJ...516..127U}    \\ 
                    &   &   S    &   $-$1.54  &   \cite{1999ApJ...516..127U}    \\ 
\object{Mrk  348}   & * &        &   $+$0.93  &   \cite{1998AJ....115..885B}    \\ 
\object{Mrk  463E}  &   &   L    &   $-$1.06  &   Norris et~al., unpublished    \\ 
                    &   &   R    &   $-$0.62  &   Norris et~al., unpublished    \\ 
                    &   &   1    &   $-$0.67  &   Norris et~al., unpublished    \\ 
                    &   &   2    &   $-$0.77  &   Norris et~al., unpublished    \\ 
                    &   &   3    &   $-$1.00  &   Norris et~al., unpublished    \\ 
\object{Mrk 1210}   &   &   NW   &   $-$1.26  &   This paper                    \\ 
                    &   &   SE   &   $-$0.78  &   This paper                    \\ 
\object{NGC 1068}   & * &   NE   &   $-$1.5   &   \cite{1998ApJ...504..147R}    \\ 
                    &   &   C    &   $>$$2.2$   &   \cite{1998ApJ...504..147R}    \\ 
                    &   &   S1   &   $>$$0.6$   &   \cite{1998ApJ...504..147R}    \\ 
                    &   &   S2   &   $<$$-1.9$  &   \cite{1998ApJ...504..147R}    \\ 
\object{NGC 2110}   & * &   C    &   $+0.12$  &   This paper                    \\ 
\object{NGC 2639}   & * &        &   $+1.78$  &   \cite{1998ApJ...505..587W}    \\ 
\object{NGC 3079}   & * &   E    &   $+0.77$  &   Middelberg et~al., in prep.    \\ 
                    &   &   A    &   $>$$+4.54$ &   Middelberg et~al., in prep.    \\ 
                    &   &   B    &   $>$$+4.36$ &   Middelberg et~al., in prep.    \\ 
\object{NGC 3147}   & * &        &   $+0.20$  &   \cite{2001ApJ...562L.133U}    \\ 
\object{NGC 4151}   & * &   E    &   $-0.5$   &   \cite{1998ApJ...496..196U}    \\ 
                    &   &   D    &   $<$$-0.2$  &   \cite{1998ApJ...496..196U}    \\ 
                    &   &   F    &   $<$$-1.3$  &   \cite{1998ApJ...496..196U}    \\ 
\object{NGC 4203}   & * &        &   $+0.38$  &   \cite{2001ApJ...562L.133U}    \\ 
\object{NGC 4579}   & * &        &   $+0.20$  &   \cite{2001ApJ...562L.133U}    \\ 
\object{NGC 5506}   & * &   B0   &   $+0.06$  &   This paper                    \\ 
                    &   &   B1   &   $-0.73$  &   This paper                    \\ 
                    &   &   B2   &   $-0.30$  &   This paper                    \\ 
\object{NGC 5793}   & * &   C1C  &   $-0.70$  &   \cite{2000AaA...360...49H}    \\ 
                    &   &   C1NE &   $-1.00$  &   \cite{2000AaA...360...49H}    \\ 
                    &   &   C2C  &   $-0.46$  &   \cite{2000AaA...360...49H}    \\ 
                    &   &   C2W  &   $-0.72$  &   \cite{2000AaA...360...49H}    \\ 
                    &   &   C2E  &   $+0.13$  &   \cite{2000AaA...360...49H}    \\ 
\object{NGC 7469}   & * &   2    &   $-0.34$  &   Norris et~al., unpublished    \\ 
                    &   &   3    &   $+0.09$  &   Norris et~al., unpublished    \\ 
                    &   &   5    &   $-0.12$  &   Norris et~al., unpublished    \\ 
\object{NGC 7674}   &   &        &   $-1.78$  &   This paper                    \\ 
\hline
\end{tabular}
\end{table}