diff --git a/acorn.js b/acorn.js
index e62febdf73..8a7f25cefc 100644
--- a/acorn.js
+++ b/acorn.js
@@ -23,7 +23,7 @@
 (function(mod) {
   if (typeof exports == "object" && typeof module == "object") return mod(exports); // CommonJS
   if (typeof define == "function" && define.amd) return define(["exports"], mod); // AMD
-  mod(self.acorn || (self.acorn = {})); // Plain browser env
+  mod(this.acorn || (this.acorn = {})); // Plain browser env
 })(function(exports) {
   "use strict";
 
diff --git a/acorn_loose.js b/acorn_loose.js
index 8c781a337d..9341a20ec6 100644
--- a/acorn_loose.js
+++ b/acorn_loose.js
@@ -32,7 +32,7 @@
 (function(mod) {
   if (typeof exports == "object" && typeof module == "object") return mod(exports, require("./acorn")); // CommonJS
   if (typeof define == "function" && define.amd) return define(["exports", "./acorn"], mod); // AMD
-  mod(self.acorn || (self.acorn = {}), self.acorn); // Plain browser env
+  mod(this.acorn || (this.acorn = {}), this.acorn); // Plain browser env
 })(function(exports, acorn) {
   "use strict";
 
diff --git a/index.html b/index.html
index 93f868240e..64b2526591 100644
--- a/index.html
+++ b/index.html
@@ -17,7 +17,7 @@ with a <a href="acorn_loose.js">error-tolerant parser</a> and an
 <a href="util/walk.js">abstract syntax tree walker</a>, defined in other files.</p>             </td>             <td class="code">               <div class="highlight"><pre><span class="p">(</span><span class="kd">function</span><span class="p">(</span><span class="nx">mod</span><span class="p">)</span> <span class="p">{</span>
   <span class="k">if</span> <span class="p">(</span><span class="k">typeof</span> <span class="nx">exports</span> <span class="o">==</span> <span class="s2">&quot;object&quot;</span> <span class="o">&amp;&amp;</span> <span class="k">typeof</span> <span class="nx">module</span> <span class="o">==</span> <span class="s2">&quot;object&quot;</span><span class="p">)</span> <span class="k">return</span> <span class="nx">mod</span><span class="p">(</span><span class="nx">exports</span><span class="p">);</span> <span class="c1">// CommonJS</span>
   <span class="k">if</span> <span class="p">(</span><span class="k">typeof</span> <span class="nx">define</span> <span class="o">==</span> <span class="s2">&quot;function&quot;</span> <span class="o">&amp;&amp;</span> <span class="nx">define</span><span class="p">.</span><span class="nx">amd</span><span class="p">)</span> <span class="k">return</span> <span class="nx">define</span><span class="p">([</span><span class="s2">&quot;exports&quot;</span><span class="p">],</span> <span class="nx">mod</span><span class="p">);</span> <span class="c1">// AMD</span>
-  <span class="nx">mod</span><span class="p">(</span><span class="nx">self</span><span class="p">.</span><span class="nx">acorn</span> <span class="o">||</span> <span class="p">(</span><span class="nx">self</span><span class="p">.</span><span class="nx">acorn</span> <span class="o">=</span> <span class="p">{}));</span> <span class="c1">// Plain browser env</span>
+  <span class="nx">mod</span><span class="p">(</span><span class="k">this</span><span class="p">.</span><span class="nx">acorn</span> <span class="o">||</span> <span class="p">(</span><span class="k">this</span><span class="p">.</span><span class="nx">acorn</span> <span class="o">=</span> <span class="p">{}));</span> <span class="c1">// Plain browser env</span>
 <span class="p">})(</span><span class="kd">function</span><span class="p">(</span><span class="nx">exports</span><span class="p">)</span> <span class="p">{</span>
   <span class="s2">&quot;use strict&quot;</span><span class="p">;</span>
 
diff --git a/util/walk.js b/util/walk.js
index ea7eea19ec..e1e02f27a1 100644
--- a/util/walk.js
+++ b/util/walk.js
@@ -3,7 +3,7 @@
 (function(mod) {
   if (typeof exports == "object" && typeof module == "object") return mod(exports); // CommonJS
   if (typeof define == "function" && define.amd) return define(["exports"], mod); // AMD
-  mod(self.acorn.walk = {}); // Plain browser env
+  mod((this.acorn || (this.acorn = {})).walk = {}); // Plain browser env
 })(function(exports) {
   "use strict";