Added missing source links to freemarker-online-tester
diff --git a/src/main/docgen/book.xml b/src/main/docgen/book.xml
index 5c456c6..e977d41 100644
--- a/src/main/docgen/book.xml
+++ b/src/main/docgen/book.xml
@@ -2048,6 +2048,14 @@
           targetdoc="githubMirrorDocgen"/>. Relevant branches:
           <literal>master</literal></para>
         </listitem>
+
+        <listitem>
+          <para><literal>freemarker-online-tester</literal>: The service
+          behind <olink targetdoc="onlineTemplateTester"/>. URL: <olink
+          targetdoc="gitOnlineTester"/>. GitHub mirror: <olink
+          targetdoc="githubMirrorOnlineTester"/>. Relevant branches:
+          <literal>master</literal></para>
+        </listitem>
       </itemizedlist>
 
       <para>There are some other FreeMarker-related repositories, such FMPP
diff --git a/src/main/docgen/docgen.cjson b/src/main/docgen/docgen.cjson
index 35f35c2..9c80282 100644
--- a/src/main/docgen/docgen.cjson
+++ b/src/main/docgen/docgen.cjson
@@ -74,6 +74,8 @@
   githubMirrorDocgen: "https://github.com/apache/incubator-freemarker-docgen"
   gitSite: "https://git-wip-us.apache.org/repos/asf/incubator-freemarker-site.git"
   githubMirrorSite: "https://github.com/apache/incubator-freemarker-site"
+  gitOnlineTester: "https://git-wip-us.apache.org/repos/asf/incubator-freemarker-online-tester.git"
+  githubMirrorOnlineTester: "https://github.com/apache/incubator-freemarker-online-tester"
   githubProject: "olink:githubMirrorFreemarker"
   githubProjectOld: "https://github.com/freemarker/"
   privateMailingList: "mailto:private@freemarker.incubator.apache.org"