diff --git a/bk001-bk010-associate-object-storage-node-quiz.xml b/bk001-bk010-associate-object-storage-node-quiz.xml
index c2a481e9..666ec775 100644
--- a/bk001-bk010-associate-object-storage-node-quiz.xml
+++ b/bk001-bk010-associate-object-storage-node-quiz.xml
@@ -6,5 +6,5 @@
   <section xml:id="day-two-object-store-quiz-schedule">
     <title>Day 2, 14:25 to 14:45</title>
     <para></para>
-  </section> 
+  </section>
 </chapter>
diff --git a/bk001-ch008-associate-network-node-quiz.xml b/bk001-ch008-associate-network-node-quiz.xml
index 61fd6307..9e3fa02a 100644
--- a/bk001-ch008-associate-network-node-quiz.xml
+++ b/bk001-ch008-associate-network-node-quiz.xml
@@ -7,5 +7,5 @@
   <section xml:id="day-two-network-quiz-schedule">
     <title>Day 2, 10:40 to 11:00</title>
     <para></para>
-  </section> 
+  </section>
 </chapter>
diff --git a/bk001-ch012-associate-review-concept.xml b/bk001-ch012-associate-review-concept.xml
index 4f10e293..7e2f5539 100644
--- a/bk001-ch012-associate-review-concept.xml
+++ b/bk001-ch012-associate-review-concept.xml
@@ -7,5 +7,5 @@
   <section xml:id="day-two-review-schedule">
     <title>Day 2, 16:00 to 17:00</title>
     <para></para>
-  </section> 
+  </section>
 </chapter>