diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 55652ecf..fcba718f 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -170,7 +170,7 @@ pages:
   <<: *sphinx
   only:
   - master
-  - 2019
+  - "2019"
   environment:
     name: docs
     url: https://laconfdev.gitlab.io/symposion_app/