diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 650d6270..5700aca9 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -74,7 +74,7 @@ jobs:
           POETRY_VERSION: 1.1.11
         run: |
           set -eu
-          pip install 'poetry==$POETRY_VERSION'
+          pip install "poetry==$POETRY_VERSION"
           poetry config virtualenvs.create true
           poetry config virtualenvs.in-project true
           poetry config installer.parallel true