diff --git a/.github/workflows/build-pdf.yml b/.github/workflows/build-pdf.yml
index 520ab51..317fbf0 100644
--- a/.github/workflows/build-pdf.yml
+++ b/.github/workflows/build-pdf.yml
@@ -17,7 +17,7 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest]
-        python-version: [3.10]
+        python-version: ["3.10"]
     steps:
     - uses: actions/checkout@v4