diff --git a/kwarc.bib b/kwarc.bib
index c466e76c..48a88bb6 100644
--- a/kwarc.bib
+++ b/kwarc.bib
@@ -66,7 +66,7 @@ @book{Anderson.2009
  title = {A taxonomy for learning, teaching, and assessing: A revision of Bloom's taxonomy of educational objectives},
  address = {New York},
  publisher = {Longman},
- isbn = {978-0321084057    },
+ isbn = {978-0321084057},
  file = {Anderson 2009 - A taxonomy for learning:Attachments/Anderson 2009 - A taxonomy for learning.pdf:application/pdf}
 }