diff --git a/errata.html b/errata.html
index 8f185b9..c68a829 100644
--- a/errata.html
+++ b/errata.html
@@ -225,9 +225,9 @@ pre {
   </p>
 
   <p>
-    <b>p.341, Exercise 12.7</b>: For "encoder" and
-    "<code>json.Encoder</code>", read "decoder" and
-    "<code>json.Decoder</code>", respectively.
+    <b>p.341, Exercise 12.7</b>: For "decoder" and
+    "<code>json.Decoder</code>", read "encoder" and
+    "<code>json.Encoder</code>", respectively.
     (Thanks to Yoshiki Shibata, 2016-08-27.)
   </p>
 
@@ -254,7 +254,7 @@ pre {
 
   <p>
     <b>p.366, Exercise 13.3</b>: For <code>bzip2.writer</code>, read <code>bzip.writer</code>.
-    (Thanks to Yoshiki Shibata, 2015-12-20.)
+    (Thanks to Yoshiki Shibata, 2016-09-05.)
   </p>
 
 </body>