...

diff --git a/helm/software/matita/nlibrary/topology/igft.ma b/helm/software/matita/nlibrary/topology/igft.ma
index 270fbb9cdefe0345916d8855c4e38a9413362347..f4cf037a555adcb46eeb3a4f1fb3aad7ebdb3260 100644 (file)
--- a/helm/software/matita/nlibrary/topology/igft.ma
+++ b/helm/software/matita/nlibrary/topology/igft.ma
@@ -29,6 +29,10 @@ is coexisting with the old one in every development release
 (named "nightly builds" in the download page of Matita) 
 with a version strictly greater than 0.5.7.
 
+To read this tutorial in the HTML version, you need a decent browser
+equipped with a unicode capable font. Use the PDF version if some
+symbols are not correctly displayed.
+
 Orienteering
 ------------