diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 426fdd9c7a0ff6a0b0b5bc82824640897343a865..d4e7d22ad488f51d100e458d405cdf1d61f1d338 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -73,6 +73,8 @@ test:
   stage: test
   image: maven:3.8.3-jdk-8
   script:
+    - git submodule update --recursive --init
+    - git -C src/main/webapp/tei-stylesheets/ checkout $TEI_STYLESHEETS_VERSION
     - mvn $MAVEN_OPTS $MAVEN_CLI_OPTS $MAVEN_DEPLOY_OPTS -U clean test
   artifacts:   
     reports: