diff --git a/docs/json.1.html b/docs/json.1.html
index 3f2a267..56fd6f2 100644
--- a/docs/json.1.html
+++ b/docs/json.1.html
@@ -538,6 +538,16 @@ <h2 id="FEATURE-In-place-editing">FEATURE: In-place editing</h2>
   "hostname": "127.0.0.1",
   "port": 8080
 }
+
+# add/update field that contains periods
+$ json -I -f config.json -e 'this["field.with.periods"]="update"'
+json: updated "config.json" in-place
+$ cat config.json
+{
+  "hostname": "127.0.0.1",
+  "port": 8080,
+  "field.with.periods": "update"
+}
 </code></pre>
 
 <p>Some limitations. Only one file at a time:</p>
diff --git a/docs/json.1.ronn b/docs/json.1.ronn
index 08ec8e4..78cec1e 100644
--- a/docs/json.1.ronn
+++ b/docs/json.1.ronn
@@ -425,6 +425,16 @@ You can edit a file in place with `-I` and `-f FILE`:
       "port": 8080
     }
 
+    # add/update field that contains periods
+    $ json -I -f config.json -e 'this["field.with.periods"]="update"'
+    json: updated "config.json" in-place
+    $ cat config.json
+    {
+      "hostname": "127.0.0.1",
+      "port": 8080,
+      "field.with.periods": "update"
+    }
+
 Some limitations. Only one file at a time:
 
     $ json -I -f foo.json -f bar.json