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@@ -155,7 +155,7 @@ <H1><A NAME="sec:boykov_kolmogorov_max_flow"></A><TT>boykov_kolmogorov_max_flow<
 found, this vertex becomes a free vertex (marked gray), and it's
 children become orphans. The adoption phase terminates if there are
 no more orphans.</P>
-<P><IMG SRC="figs/bk_max_flow.gif" NAME="Grafik2" ALIGN=LEFT WIDTH=827 HEIGHT=311 BORDER=0><BR CLEAR=LEFT><B>Details:</B></P>
+<P><IMG SRC="figs/bk_max_flow.png" NAME="Grafik2" ALIGN=LEFT WIDTH=827 HEIGHT=311 BORDER=0><BR CLEAR=LEFT><B>Details:</B></P>
 <UL>
 	<LI><P>Marking heuristics: A timestamp is stored for each vertex
 	which shows in which iteration of the algorithm the distance to the
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