diff --git a/.travis.yml b/.travis.yml
index 39b238e..4758f82 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -19,7 +19,7 @@ matrix:
       language: shell
       before_install:
          - choco install python
-         - pip install tox codecov 'sphinx>=1.5.1'
+         - pip install tox codecov 'sphinx>=1.5.1' 'sphinxcontrib-spelling>=5'
       env:
          - TOXENV=py37
          - PATH=/c/Python37:/c/Python37/Scripts:$PATH
@@ -57,7 +57,7 @@ matrix:
     - os: windows
     - os: osx
 before_install:
-    - pip install tox codecov 'sphinx>=1.5.1'
+    - pip install tox codecov 'sphinx>=1.5.1' 'sphinxcontrib-spelling>=5'
     - ./doc/generate_authors.sh --check
 script:
     - tox