Add a glossary link for material_id.

diff --git a/include/deal.II/base/types.h b/include/deal.II/base/types.h
index 17f7f90923697dc83126c1a5a6f36616d3d2ca66..3b5f5c78f09773e69c3478d7ec51711d631860aa 100644 (file)
--- a/include/deal.II/base/types.h
+++ b/include/deal.II/base/types.h
@@ -126,6 +126,9 @@ namespace types
    *
    * There is a special value, numbers::invalid_material_id that is used to
    * indicate an invalid value of this type.
+   *
+   * @see
+   * @ref GlossMaterialId "Glossary entry on material indicators"
    */
   typedef unsigned char material_id;
 }