diff --git a/docs/reference/api/ModemManager-docs.xml b/docs/reference/api/ModemManager-docs.xml
index 2c87f43a..a83e07e2 100644
--- a/docs/reference/api/ModemManager-docs.xml
+++ b/docs/reference/api/ModemManager-docs.xml
@@ -102,44 +102,40 @@
     <xi:include href="xml/mm-compat.xml"/>
   </part>
 
-  <index>
+  <chapter id="api-index-full">
     <title>Index</title>
-  </index>
-
-  <index id="api-index-full">
-    <title>API Index</title>
-    <xi:include href="xml/api-index-full.xml"><xi:fallback /></xi:include>
-  </index>
-  <index id="deprecated-api-index" role="deprecated">
-    <title>Index of deprecated API</title>
-    <xi:include href="xml/api-index-deprecated.xml"><xi:fallback /></xi:include>
-  </index>
-  <index id="api-index-1-0" role="1.0">
-    <title>Index of new core symbols in 1.0</title>
-    <xi:include href="xml/api-index-1.0.xml"><xi:fallback /></xi:include>
-  </index>
-  <index id="api-index-1-2" role="1.2">
-    <title>Index of new core symbols in 1.2</title>
-    <xi:include href="xml/api-index-1.2.xml"><xi:fallback /></xi:include>
-  </index>
-  <index id="api-index-1-4" role="1.4">
-    <title>Index of new core symbols in 1.4</title>
-    <xi:include href="xml/api-index-1.4.xml"><xi:fallback /></xi:include>
-  </index>
-  <index id="api-index-1-6" role="1.6">
-    <title>Index of new core symbols in 1.6</title>
-    <xi:include href="xml/api-index-1.6.xml"><xi:fallback /></xi:include>
-  </index>
-  <index id="api-index-1-8" role="1.8">
-    <title>Index of new core symbols in 1.8</title>
-    <xi:include href="xml/api-index-1.8.xml"><xi:fallback /></xi:include>
-  </index>
-  <index id="api-index-1-10" role="1.10">
-    <title>Index of new core symbols in 1.10</title>
-    <xi:include href="xml/api-index-1.10.xml"><xi:fallback /></xi:include>
-  </index>
-  <index id="api-index-1-12" role="1.12">
-    <title>Index of new core symbols in 1.12</title>
-    <xi:include href="xml/api-index-1.12.xml"><xi:fallback /></xi:include>
-  </index>
+    <xi:include href="xml/api-index-full.xml"></xi:include>
+  </chapter>
+  <chapter id="api-index-deprecated" role="deprecated">
+    <title>Index of deprecated symbols</title>
+    <xi:include href="xml/api-index-deprecated.xml"></xi:include>
+  </chapter>
+  <chapter id="api-index-1-0" role="1.0">
+    <title>Index of new symbols in 1.0</title>
+    <xi:include href="xml/api-index-1.0.xml"></xi:include>
+  </chapter>
+  <chapter id="api-index-1-2" role="1.2">
+    <title>Index of new symbols in 1.2</title>
+    <xi:include href="xml/api-index-1.2.xml"></xi:include>
+  </chapter>
+  <chapter id="api-index-1-4" role="1.4">
+    <title>Index of new symbols in 1.4</title>
+    <xi:include href="xml/api-index-1.4.xml"></xi:include>
+  </chapter>
+  <chapter id="api-index-1-6" role="1.6">
+    <title>Index of new symbols in 1.6</title>
+    <xi:include href="xml/api-index-1.6.xml"></xi:include>
+  </chapter>
+  <chapter id="api-index-1-8" role="1.8">
+    <title>Index of new symbols in 1.8</title>
+    <xi:include href="xml/api-index-1.8.xml"></xi:include>
+  </chapter>
+  <chapter id="api-index-1-10" role="1.10">
+    <title>Index of new symbols in 1.10</title>
+    <xi:include href="xml/api-index-1.10.xml"></xi:include>
+  </chapter>
+  <chapter id="api-index-1-12" role="1.12">
+    <title>Index of new symbols in 1.12</title>
+    <xi:include href="xml/api-index-1.12.xml"></xi:include>
+  </chapter>
 </book>