diff --git a/source/iterators.tex b/source/iterators.tex
index 94d66d08b6..7c01857320 100644
--- a/source/iterators.tex
+++ b/source/iterators.tex
@@ -223,7 +223,7 @@
 }
 
 \pnum
-\indextext{iterator!constexpr}
+\indextext{iterator!constexpr}%
 Iterators are called \defn{constexpr iterators}
 if all operations provided to satisfy iterator category operations
 are constexpr functions, except for