Add another reference.

diff --git a/include/deal.II/hp/dof_handler.h b/include/deal.II/hp/dof_handler.h
index 2bc98e2426216b9140c8e16197ce7f2fd53137cc..fa60bff75f335a3f4e9975b3f47a624fa0d7d97d 100644 (file)
--- a/include/deal.II/hp/dof_handler.h
+++ b/include/deal.II/hp/dof_handler.h
@@ -86,8 +86,11 @@ namespace hp
    * interface that do not immediate match (for example, if you have
    * $Q_2$ and $Q_3$ elements meeting at a common face), then one needs
    * to compute constraints to ensure that the resulting finite element
-   * space on the mesh remains conforming. The whole process of working
-   * with objects of this type is explained in step-27.
+   * space on the mesh remains conforming.
+   *
+   * The whole process of working with objects of this type is explained in
+   * step-27. Many of the algorithms this class implements are described
+   * in the @ref hp_paper "hp paper".
    *
    *
    * <h3>Active FE indices and their behavior under mesh refinement</h3>