diff --git a/make_documents.py b/make_documents.py
index 9d3e593c2f660e899e54638de6547bbbfac29e31..1043073f04f87e0d6f9fa27805583f8c67a199b6 100644
--- a/make_documents.py
+++ b/make_documents.py
@@ -6,7 +6,7 @@ def adapt_file(filename):
         inline = f.readline()
         while inline:
             if inline.find("pages/")>-1 and inline.find(".md")>-1:
-                inline.replace(".md", ".html")
+                inline = inline.replace(".md", ".html")
             newversion += inline
             inline = f.readline()
     with open(filename, "w") as f: