diff --git a/Segment_Delaunay_graph_2/doc_tex/Segment_Delaunay_graph_2/PkgDescription.tex b/Segment_Delaunay_graph_2/doc_tex/Segment_Delaunay_graph_2/PkgDescription.tex
index 5cf6fff0db2..a4429af9e5f 100644
--- a/Segment_Delaunay_graph_2/doc_tex/Segment_Delaunay_graph_2/PkgDescription.tex
+++ b/Segment_Delaunay_graph_2/doc_tex/Segment_Delaunay_graph_2/PkgDescription.tex
@@ -1,5 +1,6 @@
 
 \begin{ccPkgDescription}{2D Segment Delaunay Graph \label{Pkg::SegmentDelaunayGraph2}}
+\ccHowToCite{cgal:k-sdg2-06}
 \ccPkgSummary{
  An algorithm for computing the dual of a Voronoi diagram of a set
       of segments under the Euclidean metric. It is a generalization of the