diff --git a/build/ipynb2mdd.sh b/build/ipynb2mdd.sh
index 5ec9033d95887f046ef958e20eb264e18d43b79b..5b2c2ac8aaed5dc0e2b8a2836d4c0bbe882aeea7 100644
--- a/build/ipynb2mdd.sh
+++ b/build/ipynb2mdd.sh
@@ -5,15 +5,19 @@ mkdir $MD
 
 cp index.md $MD/
 cp -R img $MD/
-for d in chapter*; do
-	cp -R $d $MD/
+for f in chapter*/*; do
+	dir=$(dirname "$f")
+	if [ "${f##*.}" = "md" ] || [ "${f##*.}" = "ipynb" ]; then
+		mkdir -p $MD/$dir
+		cp $f $MD/$f
+	fi
 done
 
 for f in $MD/chapter*/*ipynb; do
-	base=$(basename $f)
-	jupyter nbconvert --to markdown $f --output "${base%%.*}.md" 
-	rm $f
+    base=$(basename $f)
+    jupyter nbconvert --to markdown $f --output "${base%%.*}.md" 
+    rm $f
 done
 
-zip -r "$MD.zip" $MD
-[ -e $MD ] && rm -rf $MD
+zip -r "$MD.zip" $MD 
+[ -e $MD ] && rm -rf $MD