diff --git a/pmg-installation.adoc b/pmg-installation.adoc
index d3601dc..5e66278 100644
--- a/pmg-installation.adoc
+++ b/pmg-installation.adoc
@@ -254,6 +254,8 @@ acquired by `apt-get update`.
 ----
 deb http://ftp.debian.org/debian stretch main contrib
 
+deb http://ftp.debian.org/debian stretch-updates main contrib
+
 # security updates
 deb http://security.debian.org stretch/updates main contrib
 ----