diff --git a/Makefile b/Makefile
index 3ae0073e46bc3378bb347fb9311c6ca6d54f4c67..df2db81b6ef8a71fdda692d418cb98224b655341 100644
--- a/Makefile
+++ b/Makefile
@@ -9,7 +9,7 @@ ebook: chapters
 include Makerules
 
 CHAPTERS= \
-	01-intro
+	01-intro \
 	02-perfect
 
 chapters: