diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index b536a8934..74b756e7d 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -26,14 +26,16 @@ For [IntelliJ IDEA](https://www.jetbrains.com/idea/) users: the coding style is
 `.idea` folder. If you import this project into IntelliJ this style will used automatically. 
 
 Moreover (since this project is about static code analysis :wink:) a configuration for the following static code
-analysis tools is defined in the `etc` folder:
+analysis tools is defined in the POM and the `etc` and `.idea` folders:
 - [Checkstyle](http://checkstyle.sourceforge.net/)
-- [PMD](http://https://pmd.github.io/)
+- [PMD](https://pmd.github.io/)
 - [FindBugs](http://findbugs.sourceforge.net/) and [SpotBugs](https://spotbugs.github.io)
+- [Error Prone](http://errorprone.info)
 - [IntelliJ](https://www.jetbrains.com/help/idea/code-inspection.html)
 
 This configuration will be picked up automatically if you build the project using maven. If you install the CheckStyle 
-plugin of IntelliJ then the correct set of CheckStyle rules will used automatically. 
+plugin of IntelliJ then the correct set of CheckStyle rules will used automatically. Moreover, the code formatter and 
+the inspection rules will be automatically picked up bey IntelliJ.
 
 ## Proposing Changes
 
diff --git a/etc/pmd-configuration.xml b/etc/pmd-configuration.xml
index a81a260bf..0765610c9 100644
--- a/etc/pmd-configuration.xml
+++ b/etc/pmd-configuration.xml
@@ -169,7 +169,6 @@
   <rule ref="rulesets/java/javabeans.xml/MissingSerialVersionUID"/>
   <rule ref="rulesets/java/junit.xml/JUnitStaticSuite"/>
   <rule ref="rulesets/java/junit.xml/JUnitSpelling"/>
-  <rule ref="rulesets/java/junit.xml/JUnitAssertionsShouldIncludeMessage"/>
   <rule ref="rulesets/java/junit.xml/UnnecessaryBooleanAssertion"/>
   <rule ref="rulesets/java/junit.xml/UseAssertEqualsInsteadOfAssertTrue"/>
   <rule ref="rulesets/java/junit.xml/UseAssertSameInsteadOfAssertTrue"/>
@@ -228,7 +227,7 @@
   <rule ref="rulesets/java/naming.xml/AvoidFieldNameMatchingTypeName"/>
   <rule ref="rulesets/java/naming.xml/NoPackage"/>
   <rule ref="rulesets/java/naming.xml/PackageCase"/>
-  <rule ref="rulesets/java/naming.xml/MisleadingVariableName"/>
+  <rule ref="rulesets/java/naming.xml/MIsLeadingVariableName"/>
   <rule ref="rulesets/java/naming.xml/GenericsNaming"/>
   <rule ref="rulesets/java/codesize.xml/NPathComplexity"/>
   <rule ref="rulesets/java/codesize.xml/ExcessiveClassLength"/>