diff --git a/lab000-virtualbox-basics.xml b/lab000-virtualbox-basics.xml
index 4c954b3a..92e9fd9f 100644
--- a/lab000-virtualbox-basics.xml
+++ b/lab000-virtualbox-basics.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE chapter [
-<!-- Some useful entities borrowed from HTML -->
-<!ENTITY nbsp "&#160;">
+<!ENTITY % openstack SYSTEM "../common/entities/openstack.ent">
+%openstack;
 ]>
 <chapter xmlns="http://docbook.org/ns/docbook"
   xmlns:xi="http://www.w3.org/2001/XInclude"
diff --git a/module003-ch006-more-concepts.xml b/module003-ch006-more-concepts.xml
index d3ded816..03e6b20e 100644
--- a/module003-ch006-more-concepts.xml
+++ b/module003-ch006-more-concepts.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE chapter [
-<!-- Some useful entities borrowed from HTML -->
-<!ENTITY nbsp "&#160;">
+<!ENTITY % openstack SYSTEM "../common/entities/openstack.ent">
+%openstack;
 ]>
 <chapter xmlns="http://docbook.org/ns/docbook"
     xmlns:xi="http://www.w3.org/2001/XInclude"
diff --git a/module003-ch007-swift-cluster-architecture.xml b/module003-ch007-swift-cluster-architecture.xml
index c2381d6f..0469cb6d 100644
--- a/module003-ch007-swift-cluster-architecture.xml
+++ b/module003-ch007-swift-cluster-architecture.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE section [
-<!-- Some useful entities borrowed from HTML -->
-<!ENTITY nbsp "&#160;">
+<!ENTITY % openstack SYSTEM "../common/entities/openstack.ent">
+%openstack;
 ]>
 <chapter xmlns="http://docbook.org/ns/docbook"
     xmlns:xi="http://www.w3.org/2001/XInclude"