diff --git a/js/build_page.js b/js/build_page.js
index 2704794..6a2ee0a 100644
--- a/js/build_page.js
+++ b/js/build_page.js
@@ -125,7 +125,7 @@
         var classeDiv;
         
         // Check if the subject is repeated
-        if (i < classes.length - 1) duplicateSubjectBoolNext = classes[i+1].classe.friendly_name == classe.friendly_name;
+        if (i < classes.length - 1) duplicateSubjectBoolNext = classes[i+1].friendly_name == classe.friendly_name;
         else duplicateSubjectBoolNext = false;
         if (i > 0) duplicateSubjectBoolPrev = classes[i-1].friendly_name == classe.friendly_name;
         else duplicateSubjectBoolPrev = false;