Okio proguard rules link

website/index.html

@@ -171,7 +171,7 @@ <h4>Gradle</h4>
               <p>Retrofit requires at minimum Java 7 or Android 2.3.</p>
 
               <h4>ProGuard</h4>
-              <p>If you are using Proguard in your project add the following lines to your configuration:</p>
+              <p>If you are using ProGuard in your project add the following lines to your configuration:</p>
               <pre class="prettyprint">
 # Platform calls Class.forName on types which do not exist on Android to determine platform.
 -dontnote retrofit2.Platform
@@ -182,6 +182,7 @@ <h4>ProGuard</h4>
 # Retain declared checked exceptions for use by a Proxy instance.
 -keepattributes Exceptions
 </pre>
+            <p>Retrofit uses <a href="https://github.com/square/okio">Okio</a> under the hood, so you may want to look at its <a href="https://github.com/square/okio#proguard">ProGuard rules</a> as well.</p>
             </section>
 
             <section id="contributing">