diff --git a/source/regex.tex b/source/regex.tex
index a4422ef8ef..fd6292e34e 100644
--- a/source/regex.tex
+++ b/source/regex.tex
@@ -3929,7 +3929,7 @@
 value that can be held in an object of type \tcode{charT} the translator shall
 throw an exception object of type \tcode{regex_error}.
 \begin{note}
-This means that values of the form \tcode{"uxxxx"} that do not fit in
+This means that values of the form \tcode{"\textbackslash{}uxxxx"} that do not fit in
 a character are invalid.
 \end{note}