diff --git a/.travis.yml b/.travis.yml
index 768d5ff5..e63958f9 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -8,7 +8,7 @@ addons:
     sources:
       - deadsnakes
     packages:
-    - python3.8
+    - python3.7
     - libmagic1
     - libmagic-dev
 script:
@@ -23,6 +23,8 @@ before_install:
   - sudo apt-get install python3 python3-pip python3-setuptools
   - rvm install 2.6.0
   - rvm use 2.6.0
+  - python --version
+  - pip3 --version
 install:
   - gem install pdd -v 0.20.5
   - gem install est -v 0.3.4
diff --git a/pom.xml b/pom.xml
index 4e4ea687..731a0228 100644
--- a/pom.xml
+++ b/pom.xml
@@ -218,7 +218,6 @@ OF THE POSSIBILITY OF SUCH DAMAGE.
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-javadoc-plugin</artifactId>
         <configuration>
-          <source>8</source>
           <tags>
             <tag>
               <name>todo</name>