diff --git a/Manual/doc_tex/Introduction_ref/thirdparty.tex b/Manual/doc_tex/Introduction_ref/thirdparty.tex
index 6649c058e37..3f0ede59f5f 100644
--- a/Manual/doc_tex/Introduction_ref/thirdparty.tex
+++ b/Manual/doc_tex/Introduction_ref/thirdparty.tex
@@ -44,12 +44,19 @@ It is only available commercially from \path'www.algorithmic-solutions.com'.
 A library of sparse linear solvers.
 It can be used by the \ccc{Surface_mesh_parametrization} package
 in order to speed up the algorithm. you can download it from
- \path'www.tau.ac.il/\~stoledo/taucs/'.
+ \path'http://www.tau.ac.il/~stoledo/taucs/'.
+
 
 \subsection{OpenNL \label{thirdparty:OpenNL}}
 
-A solver.
-OpenNL is distributed together with \cgal.
+OpenNL (Open Numerical Library) is a library to easily construct and solve
+sparse linear systems. It is the default solver of the
+\ccc{Surface_mesh_parametrization} package.
+
+The author is Bruno Levy <bruno.levy@loria.fr>.
+OpenNL main page is \path'http://www.loria.fr/~levy/software/'.
+
+\cgal\ includes a version of OpenNL in C++, made especially for \cgal\ by Bruno Levy.
 
 
 \subsection{zlib \label{thirdparty:zlib}}