diff --git a/.travis.yml b/.travis.yml
index 961f8d2..08e9732 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -9,6 +9,8 @@ matrix:
     - r: 3.3
       addons:
         apt:
+          sources:
+            - sourceline: 'ppa:cran/travis'
           packages: libnode-dev
     - r: release
     - r: release