diff --git a/source/threads.tex b/source/threads.tex
index a898419ceb..14c5aa4285 100644
--- a/source/threads.tex
+++ b/source/threads.tex
@@ -3546,7 +3546,7 @@
 
 \begin{itemdecl}
 template<class U>
-  constexpr atomic_ref(const atomic_ref<U>&) noexcept;
+  constexpr atomic_ref(const atomic_ref<U>& ref) noexcept;
 \end{itemdecl}
 
 \begin{itemdescr}