diff --git a/.travis.yml b/.travis.yml
index 4c8d19e..732228a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,14 +7,14 @@ rust:
 
 env:
   - TEST_COMMAND=test FEATURES=''
-  - TEST_COMMAND=test FEATURES=--features="serde"
+  - TEST_COMMAND=test FEATURES='--features=serde'
 
 matrix:
   include:
     - rust: nightly
-      env: TEST_COMMAND=build FEATURES="--no-default-features --features=u32_backend"
+      env: TEST_COMMAND=build FEATURES='--no-default-features --features=u32_backend'
     - rust: nightly
-      env: TEST_COMMAND=test FEATURES=--features="nightly"
+      env: TEST_COMMAND=test FEATURES='--features=nightly'
 
 script:
   - cargo $TEST_COMMAND $FEATURES