diff --git a/.github/workflows/publish_api_documentation.yml b/.github/workflows/publish_api_documentation.yml
index e63a2adc..5f714234 100644
--- a/.github/workflows/publish_api_documentation.yml
+++ b/.github/workflows/publish_api_documentation.yml
@@ -14,6 +14,8 @@ jobs:
 
     steps:
     - uses: actions/checkout@v2
+      - with:
+          ref: 3.0
     - uses: actions/setup-python@v2
       with:
         python-version: 3.6