Verbatim source notice from
RTL/Component/Generators/Glyph2D/CIFXQuadEdge.cpp in U3D 1.5.2:

This code in this module is a modification of the code from the
article "Incremental Delaunay Triangulation" by Dani Lischinski
(danix@graphics.cornell.edu) in "Graphics Gems IV", Academic
Press, 1994, p. 47-59, code: p. 51-58.  The actual source is
available from www.acm.org/pubs/tog/GraphicsGems/gemsiv.zip
in the "delaunay" folder.  The associated website's root address
is www.graphicsgems.org.  It states that the Graphics Gems code
can be used without restrictions.
