diff --git a/.travis.sh b/.travis.sh
index d49b6acfb4943808b4b21f5d61ca034bf95b2474..8f5d5fcfeb80152b571cbfcf57c853cc96265d94 100755
--- a/.travis.sh
+++ b/.travis.sh
@@ -53,7 +53,7 @@ pushd /tmp
 mkdocs new test && cd test
 
 # Test Docker image build
-docker run --rm -it -v `pwd`:/docs $TRAVIS_REPO_SLUG build --theme material
+docker run --rm -it -v $(pwd):/docs $TRAVIS_REPO_SLUG build --theme material
 
 # Return to original directory
 popd