Prefer https over http
diff --git a/Makefile.am b/Makefile.am
index 33406e2..1cfae75 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -4,7 +4,7 @@
 #  You may not use this file except in compliance with the License.  You may
 #  obtain a copy of the License at
 #
-#    http://www.imagemagick.org/script/license.php
+#    https://www.imagemagick.org/script/license.php
 #
 #  Unless required by applicable law or agreed to in writing, software
 #  distributed under the License is distributed on an "AS IS" BASIS,