diff --git a/source/utilities.tex b/source/utilities.tex
index 2e122c6dec..5172585905 100644
--- a/source/utilities.tex
+++ b/source/utilities.tex
@@ -1549,7 +1549,7 @@
 
   // \tcode{ignore}
   struct @\exposidnc{ignore-type}@ {                      // \expos
-    constexpr const @\exposid{ignore-type}@
+    constexpr const @\exposid{ignore-type}@&
       operator=(const auto &) const noexcept { return *this; }
   };
   inline constexpr @\exposid{ignore-type}@ ignore;