diff --git a/errata.html b/errata.html
index a907c83..6548863 100644
--- a/errata.html
+++ b/errata.html
@@ -65,6 +65,12 @@ pre {
     (Corrected in the second printing.)
   </p>
 
+  <p>
+    <b>p.52, ¶9</b>: for "The integer arithmetic operators", read
+    "The arithmetic operators".
+    (Thanks to Yoshiki Shibata, 2015-12-20.)
+  </p>
+
   <p>
     <b>p.68</b>: the table of UTF-8 encodings is missing a bit from each first byte.
     The corrected table is shown below.