Add a link for std::span.

diff --git a/include/deal.II/base/array_view.h b/include/deal.II/base/array_view.h
index 9a271eb63f357a3887a99be9b9c834dd47d6fad9..f35415803ab6249d8ae092d30479ac3feca87119 100644 (file)
--- a/include/deal.II/base/array_view.h
+++ b/include/deal.II/base/array_view.h
@@ -67,8 +67,9 @@ DEAL_II_NAMESPACE_OPEN
  * therefore changes the std::vector object itself -- consequently, the
  * std::vector::operator[] is non-@p const.
  *
- * @note This class is similar to std::span, but the latter is only
- *  available in C++20.
+ * @note This class is similar to
+ *   [`std::span`](https://en.cppreference.com/w/cpp/container/span), but the
+ *   latter is only available starting in C++20.
  *
  * @ingroup data
  */