diff --git a/src/CSSList/Document.php b/src/CSSList/Document.php
index 8bf15b9e..33a9bad6 100644
--- a/src/CSSList/Document.php
+++ b/src/CSSList/Document.php
@@ -127,7 +127,7 @@ public function createShorthands()
     }
 
     /**
-     * Override render() to make format argument optional
+     * Override `render()` to make format argument optional
      *
      * @param OutputFormat|null $oOutputFormat
      *
diff --git a/src/CSSList/KeyFrame.php b/src/CSSList/KeyFrame.php
index b7a0afb8..d9420e9c 100644
--- a/src/CSSList/KeyFrame.php
+++ b/src/CSSList/KeyFrame.php
@@ -68,8 +68,6 @@ public function __toString()
     }
 
     /**
-     * @param OutputFormat $oOutputFormat
-     *
      * @return string
      */
     public function render(OutputFormat $oOutputFormat)
diff --git a/src/Property/CSSNamespace.php b/src/Property/CSSNamespace.php
index 30957970..dbd279ac 100644
--- a/src/Property/CSSNamespace.php
+++ b/src/Property/CSSNamespace.php
@@ -33,14 +33,15 @@ public function getLineNo()
         return $this->iLineNo;
     }
 
+    /**
+     * @return string
+     */
     public function __toString()
     {
         return $this->render(new OutputFormat());
     }
 
     /**
-     * @param OutputFormat $oOutputFormat
-     *
      * @return string
      */
     public function render(OutputFormat $oOutputFormat)
diff --git a/src/Property/Charset.php b/src/Property/Charset.php
index 5c0c65fb..3ee0c3d0 100644
--- a/src/Property/Charset.php
+++ b/src/Property/Charset.php
@@ -76,8 +76,6 @@ public function __toString()
     }
 
     /**
-     * @param OutputFormat $oOutputFormat
-     *
      * @return string
      */
     public function render(OutputFormat $oOutputFormat)
diff --git a/src/Property/Import.php b/src/Property/Import.php
index beca0ff2..c8e6bfc1 100644
--- a/src/Property/Import.php
+++ b/src/Property/Import.php
@@ -61,14 +61,15 @@ public function getLocation()
         return $this->oLocation;
     }
 
+    /**
+     * @return string
+     */
     public function __toString()
     {
         return $this->render(new OutputFormat());
     }
 
     /**
-     * @param OutputFormat $oOutputFormat
-     *
      * @return string
      */
     public function render(OutputFormat $oOutputFormat)
diff --git a/src/Renderable.php b/src/Renderable.php
index c21bf19e..dc1bff3c 100644
--- a/src/Renderable.php
+++ b/src/Renderable.php
@@ -10,11 +10,12 @@ interface Renderable
     public function __toString();
 
     /**
-     * @param OutputFormat $oOutputFormat
-     *
      * @return string
      */
     public function render(OutputFormat $oOutputFormat);
 
+    /**
+     * @return int
+     */
     public function getLineNo();
 }
diff --git a/src/RuleSet/AtRuleSet.php b/src/RuleSet/AtRuleSet.php
index 94179208..88bc5bd3 100644
--- a/src/RuleSet/AtRuleSet.php
+++ b/src/RuleSet/AtRuleSet.php
@@ -48,14 +48,15 @@ public function atRuleArgs()
         return $this->sArgs;
     }
 
+    /**
+     * @return string
+     */
     public function __toString()
     {
         return $this->render(new OutputFormat());
     }
 
     /**
-     * @param OutputFormat $oOutputFormat
-     *
      * @return string
      */
     public function render(OutputFormat $oOutputFormat)
diff --git a/src/RuleSet/RuleSet.php b/src/RuleSet/RuleSet.php
index 614ed6f7..3030c7d9 100644
--- a/src/RuleSet/RuleSet.php
+++ b/src/RuleSet/RuleSet.php
@@ -224,14 +224,15 @@ public function removeRule($mRule)
         }
     }
 
+    /**
+     * @return string
+     */
     public function __toString()
     {
         return $this->render(new OutputFormat());
     }
 
     /**
-     * @param OutputFormat $oOutputFormat
-     *
      * @return string
      */
     public function render(OutputFormat $oOutputFormat)
diff --git a/src/Value/CSSFunction.php b/src/Value/CSSFunction.php
index 98cbf02e..4a217304 100644
--- a/src/Value/CSSFunction.php
+++ b/src/Value/CSSFunction.php
@@ -37,14 +37,15 @@ public function getArguments()
         return $this->aComponents;
     }
 
+    /**
+     * @return string
+     */
     public function __toString()
     {
         return $this->render(new OutputFormat());
     }
 
     /**
-     * @param OutputFormat $oOutputFormat
-     *
      * @return string
      */
     public function render(OutputFormat $oOutputFormat)
diff --git a/src/Value/CSSString.php b/src/Value/CSSString.php
index bf99461f..e38eecf1 100644
--- a/src/Value/CSSString.php
+++ b/src/Value/CSSString.php
@@ -61,14 +61,15 @@ public function getString()
         return $this->sString;
     }
 
+    /**
+     * @return string
+     */
     public function __toString()
     {
         return $this->render(new OutputFormat());
     }
 
     /**
-     * @param OutputFormat $oOutputFormat
-     *
      * @return string
      */
     public function render(OutputFormat $oOutputFormat)
diff --git a/src/Value/CalcRuleValueList.php b/src/Value/CalcRuleValueList.php
index 5e3e4bde..d48e0ab9 100644
--- a/src/Value/CalcRuleValueList.php
+++ b/src/Value/CalcRuleValueList.php
@@ -15,8 +15,6 @@ public function __construct($iLineNo = 0)
     }
 
     /**
-     * @param OutputFormat $oOutputFormat
-     *
      * @return string
      */
     public function render(OutputFormat $oOutputFormat)
diff --git a/src/Value/Color.php b/src/Value/Color.php
index f3f2b29c..9ec4c4c6 100644
--- a/src/Value/Color.php
+++ b/src/Value/Color.php
@@ -105,14 +105,15 @@ public function getColorDescription()
         return $this->getName();
     }
 
+    /**
+     * @return string
+     */
     public function __toString()
     {
         return $this->render(new OutputFormat());
     }
 
     /**
-     * @param OutputFormat $oOutputFormat
-     *
      * @return string
      */
     public function render(OutputFormat $oOutputFormat)
diff --git a/src/Value/LineName.php b/src/Value/LineName.php
index 1fdd9507..7af9391e 100644
--- a/src/Value/LineName.php
+++ b/src/Value/LineName.php
@@ -36,14 +36,15 @@ public static function parse(ParserState $oParserState)
         return new LineName($aNames, $oParserState->currentLine());
     }
 
+    /**
+     * @return string
+     */
     public function __toString()
     {
         return $this->render(new OutputFormat());
     }
 
     /**
-     * @param OutputFormat $oOutputFormat
-     *
      * @return string
      */
     public function render(OutputFormat $oOutputFormat)
diff --git a/src/Value/Size.php b/src/Value/Size.php
index f07b8e91..ff592c12 100644
--- a/src/Value/Size.php
+++ b/src/Value/Size.php
@@ -141,14 +141,15 @@ public function isRelative()
         return false;
     }
 
+    /**
+     * @return string
+     */
     public function __toString()
     {
         return $this->render(new OutputFormat());
     }
 
     /**
-     * @param OutputFormat $oOutputFormat
-     *
      * @return string
      */
     public function render(OutputFormat $oOutputFormat)
diff --git a/src/Value/URL.php b/src/Value/URL.php
index 31d86819..26417063 100644
--- a/src/Value/URL.php
+++ b/src/Value/URL.php
@@ -42,14 +42,15 @@ public function getURL()
         return $this->oURL;
     }
 
+    /**
+     * @return string
+     */
     public function __toString()
     {
         return $this->render(new OutputFormat());
     }
 
     /**
-     * @param OutputFormat $oOutputFormat
-     *
      * @return string
      */
     public function render(OutputFormat $oOutputFormat)
diff --git a/src/Value/ValueList.php b/src/Value/ValueList.php
index c7156089..514f401e 100644
--- a/src/Value/ValueList.php
+++ b/src/Value/ValueList.php
@@ -48,14 +48,15 @@ public function setListSeparator($sSeparator)
         $this->sSeparator = $sSeparator;
     }
 
+    /**
+     * @return string
+     */
     public function __toString()
     {
         return $this->render(new OutputFormat());
     }
 
     /**
-     * @param OutputFormat $oOutputFormat
-     *
      * @return string
      */
     public function render(OutputFormat $oOutputFormat)