diff --git a/build.sh b/build.sh
index 7a02b0c..b963aca 100755
--- a/build.sh
+++ b/build.sh
@@ -14,7 +14,7 @@ rm --force --recursive "${OUTPUT}"
 mkdir --parents "${OUTPUT}"
 
 for file in $(cat "${INPUTS}") ; do
-    files+=("${INPUT}/${f}.md")
+    files+=("${INPUT}/${file}.md")
 done
 
 pandoc \