diff --git a/src/PhpSpreadsheet/Calculation/MathTrig.php b/src/PhpSpreadsheet/Calculation/MathTrig.php
index 45a32da0..8a4310cb 100644
--- a/src/PhpSpreadsheet/Calculation/MathTrig.php
+++ b/src/PhpSpreadsheet/Calculation/MathTrig.php
@@ -1212,27 +1212,28 @@ class MathTrig
         return $returnValue;
     }
 
- 	/**
-	 *	SUMIFS
-	 *
-	 *	Counts the number of cells that contain numbers within the list of arguments
-	 *
-	 *	Excel Function:
-	 *		SUMIFS(value1[,value2[, ...]],condition)
-	 *
-	 *	@access	public
-	 *	@category Mathematical and Trigonometric Functions
-	 *	@param	mixed		$arg,...		Data values
-	 *	@param	string		$condition		The criteria that defines which cells will be summed.
-	 *	@return	float
-	 */
-	public static function SUMIFS() {
-		$arrayList = func_get_args();
+     /**
+     *    SUMIFS
+     *
+     *    Counts the number of cells that contain numbers within the list of arguments
+     *
+     *    Excel Function:
+     *        SUMIFS(value1[,value2[, ...]],condition)
+     *
+     *    @access    public
+     *    @category Mathematical and Trigonometric Functions
+     *    @param    mixed        $arg,...        Data values
+     *    @param    string        $condition        The criteria that defines which cells will be summed.
+     *    @return    float
+     */
+    public static function SUMIFS()
+    {
+        $arrayList = func_get_args();
 
-		// Return value
-		$returnValue = 0;
+        // Return value
+        $returnValue = 0;
 
-		$sumArgs = Functions::flattenArray(array_shift($arrayList));
+        $sumArgs = Functions::flattenArray(array_shift($arrayList));
 
         while (count($arrayList) > 0) {
             $aArgsArray[] = Functions::flattenArray(array_shift($arrayList));
@@ -1256,9 +1257,9 @@ class MathTrig
             }
         }
 
-		// Return
-		return $returnValue;
-	}
+        // Return
+        return $returnValue;
+    }
 
     /**
      * SUMPRODUCT
diff --git a/src/PhpSpreadsheet/Helper/HTML.php b/src/PhpSpreadsheet/Helper/HTML.php
index 703bf20b..8e7de536 100644
--- a/src/PhpSpreadsheet/Helper/HTML.php
+++ b/src/PhpSpreadsheet/Helper/HTML.php
@@ -634,7 +634,7 @@ class HTML
 
     protected function cleanWhitespace()
     {
-        foreach($this->richTextObject->getRichTextElements() as $key => $element) {
+        foreach ($this->richTextObject->getRichTextElements() as $key => $element) {
             $text = $element->getText();
             // Trim any leading spaces on the first run
             if ($key == 0) {
diff --git a/src/PhpSpreadsheet/Reader/Excel5/Color/BIFF5.php b/src/PhpSpreadsheet/Reader/Excel5/Color/BIFF5.php
index 89f83fd2..67985721 100644
--- a/src/PhpSpreadsheet/Reader/Excel5/Color/BIFF5.php
+++ b/src/PhpSpreadsheet/Reader/Excel5/Color/BIFF5.php
@@ -76,4 +76,4 @@ class BIFF5
         }
         return array('rgb' => '000000');
     }
-}
\ No newline at end of file
+}
diff --git a/src/PhpSpreadsheet/Reader/Excel5/Color/BuiltIn.php b/src/PhpSpreadsheet/Reader/Excel5/Color/BuiltIn.php
index 237a1e8c..bb7adb85 100644
--- a/src/PhpSpreadsheet/Reader/Excel5/Color/BuiltIn.php
+++ b/src/PhpSpreadsheet/Reader/Excel5/Color/BuiltIn.php
@@ -30,4 +30,4 @@ class BuiltIn
         }
         return array('rgb' => '000000');
     }
-}
\ No newline at end of file
+}
diff --git a/src/PhpSpreadsheet/Reader/Excel5/ErrorCode.php b/src/PhpSpreadsheet/Reader/Excel5/ErrorCode.php
index b9996ed1..79e28f39 100644
--- a/src/PhpSpreadsheet/Reader/Excel5/ErrorCode.php
+++ b/src/PhpSpreadsheet/Reader/Excel5/ErrorCode.php
@@ -27,4 +27,4 @@ class ErrorCode
         }
         return false;
     }
-}
\ No newline at end of file
+}
diff --git a/src/PhpSpreadsheet/Reader/Excel5/Style/Border.php b/src/PhpSpreadsheet/Reader/Excel5/Style/Border.php
index 6cb07bfe..9d63aa07 100644
--- a/src/PhpSpreadsheet/Reader/Excel5/Style/Border.php
+++ b/src/PhpSpreadsheet/Reader/Excel5/Style/Border.php
@@ -2,25 +2,25 @@
 
 namespace PHPExcel\Reader\Excel5\Style;
 
-use \PHPExcel\Style\Border;
+use \PHPExcel\Style\Border as StyleBorder;
 
 class Border
 {
     protected static $map = array(
-        0x00 => Border::BORDER_NONE,
-        0x01 => Border::BORDER_THIN,
-        0x02 => Border::BORDER_MEDIUM,
-        0x03 => Border::BORDER_DASHED,
-        0x04 => Border::BORDER_DOTTED,
-        0x05 => Border::BORDER_THICK,
-        0x06 => Border::BORDER_DOUBLE,
-        0x07 => Border::BORDER_HAIR,
-        0x08 => Border::BORDER_MEDIUMDASHED,
-        0x09 => Border::BORDER_DASHDOT,
-        0x0A => Border::BORDER_MEDIUMDASHDOT,
-        0x0B => Border::BORDER_DASHDOTDOT,
-        0x0C => Border::BORDER_MEDIUMDASHDOTDOT,
-        0x0D => Border::BORDER_SLANTDASHDOT,
+        0x00 => StyleBorder::BORDER_NONE,
+        0x01 => StyleBorder::BORDER_THIN,
+        0x02 => StyleBorder::BORDER_MEDIUM,
+        0x03 => StyleBorder::BORDER_DASHED,
+        0x04 => StyleBorder::BORDER_DOTTED,
+        0x05 => StyleBorder::BORDER_THICK,
+        0x06 => StyleBorder::BORDER_DOUBLE,
+        0x07 => StyleBorder::BORDER_HAIR,
+        0x08 => StyleBorder::BORDER_MEDIUMDASHED,
+        0x09 => StyleBorder::BORDER_DASHDOT,
+        0x0A => StyleBorder::BORDER_MEDIUMDASHDOT,
+        0x0B => StyleBorder::BORDER_DASHDOTDOT,
+        0x0C => StyleBorder::BORDER_MEDIUMDASHDOTDOT,
+        0x0D => StyleBorder::BORDER_SLANTDASHDOT,
     );
 
     /**
@@ -35,6 +35,6 @@ class Border
         if (isset(self::$map[$index])) {
             return self::$map[$index];
         }
-        return Border::BORDER_NONE;
+        return StyleBorder::BORDER_NONE;
     }
-}
\ No newline at end of file
+}
diff --git a/src/PhpSpreadsheet/Reader/Excel5/Style/FillPattern.php b/src/PhpSpreadsheet/Reader/Excel5/Style/FillPattern.php
index 3b929836..c386b30b 100644
--- a/src/PhpSpreadsheet/Reader/Excel5/Style/FillPattern.php
+++ b/src/PhpSpreadsheet/Reader/Excel5/Style/FillPattern.php
@@ -42,4 +42,4 @@ class FillPattern
         }
         return Fill::FILL_NONE;
     }
-}
\ No newline at end of file
+}
diff --git a/src/PhpSpreadsheet/Shared/CodePage.php b/src/PhpSpreadsheet/Shared/CodePage.php
index ea5f9c00..24f4b634 100644
--- a/src/PhpSpreadsheet/Shared/CodePage.php
+++ b/src/PhpSpreadsheet/Shared/CodePage.php
@@ -118,10 +118,10 @@ class CodePage
                 return 'CP950';    //    Macintosh Chinese Traditional
             case 10003:
                 return 'CP1361';   //    Macintosh Korean
-            case 10004:	
-                return 'MACARABIC';  //	Apple Arabic
+            case 10004:
+                return 'MACARABIC'; //    Apple Arabic
             case 10005:
-                return 'MACHEBREW';		//	Apple Hebrew
+                return 'MACHEBREW'; //    Apple Hebrew
             case 10006:
                 return 'MACGREEK';  //    Macintosh Greek
             case 10007:
@@ -129,11 +129,11 @@ class CodePage
             case 10008:
                 return 'CP936';  //    Macintosh - Simplified Chinese (GB 2312)
             case 10010:
-                return 'MACROMANIA';	//	Macintosh Romania
+                return 'MACROMANIA';    //    Macintosh Romania
             case 10017:
-                return 'MACUKRAINE';	//	Macintosh Ukraine
+                return 'MACUKRAINE';    //    Macintosh Ukraine
             case 10021:
-                return 'MACTHAI';	//	Macintosh Thai
+                return 'MACTHAI';    //    Macintosh Thai
             case 10029:
                 return 'MACCENTRALEUROPE';  //    Macintosh Central Europe
             case 10079:
@@ -141,7 +141,7 @@ class CodePage
             case 10081:
                 return 'MACTURKISH';  //    Macintosh Turkish
             case 10082:
-                return 'MACCROATIAN';	//	Macintosh Croatian
+                return 'MACCROATIAN';    //    Macintosh Croatian
             case 21010:
                 return 'UTF-16LE';  //    UTF-16 (BIFF8) This isn't correct, but some Excel writer libraries erroneously use Codepage 21010 for UTF-16LE
             case 32768:
diff --git a/src/PhpSpreadsheet/Shared/ZipArchive.php b/src/PhpSpreadsheet/Shared/ZipArchive.php
index 981eeebd..7b7d9c8e 100644
--- a/src/PhpSpreadsheet/Shared/ZipArchive.php
+++ b/src/PhpSpreadsheet/Shared/ZipArchive.php
@@ -154,7 +154,8 @@ class ZipArchive
         return $contents;
     }
 
-    public function getFromIndex($index) {
+    public function getFromIndex($index)
+    {
         $extracted = $this->zip->extractByIndex($index, PCLZIP_OPT_EXTRACT_AS_STRING);
         $contents = '';
         if ((is_array($extracted)) && ($extracted != 0)) {
diff --git a/src/PhpSpreadsheet/Spreadsheet.php b/src/PhpSpreadsheet/Spreadsheet.php
index a2d27a23..eee9245e 100644
--- a/src/PhpSpreadsheet/Spreadsheet.php
+++ b/src/PhpSpreadsheet/Spreadsheet.php
@@ -238,7 +238,7 @@ class Spreadsheet
     {
         $returnData = null;
         $what = strtolower($what);
-        switch ($what){
+        switch ($what) {
             case 'all':
                 $returnData = $this->ribbonXMLData;
                 break;
@@ -282,7 +282,7 @@ class Spreadsheet
     {
         $ReturnData = null;
         $What = strtolower($What);
-        switch($What) {
+        switch ($What) {
             case 'all':
                 return $this->ribbonBinObjects;
                 break;
diff --git a/src/PhpSpreadsheet/Style/NumberFormat.php b/src/PhpSpreadsheet/Style/NumberFormat.php
index c199fffd..13a23b3e 100644
--- a/src/PhpSpreadsheet/Style/NumberFormat.php
+++ b/src/PhpSpreadsheet/Style/NumberFormat.php
@@ -447,11 +447,13 @@ class NumberFormat extends Supervisor implements \PHPExcel\IComparable
             'h'  => 'g'
         );
 
-    private static function setLowercaseCallback($matches) {
+    private static function setLowercaseCallback($matches)
+    {
         return mb_strtolower($matches[0]);
     }
 
-    private static function escapeQuotesCallback($matches) {
+    private static function escapeQuotesCallback($matches)
+    {
         return '\\' . implode('\\', str_split($matches[1]));
     }
 
@@ -468,7 +470,7 @@ class NumberFormat extends Supervisor implements \PHPExcel\IComparable
 
         // Only process the non-quoted blocks for date format characters
         $blocks = explode('"', $format);
-        foreach($blocks as $key => &$block) {
+        foreach ($blocks as $key => &$block) {
             if ($key % 2 == 0) {
                 $block = strtr($block, self::$dateFormatReplacements);
                 if (!strpos($block, 'A')) {
diff --git a/src/PhpSpreadsheet/Writer/Excel2007/ContentTypes.php b/src/PhpSpreadsheet/Writer/Excel2007/ContentTypes.php
index 7eb7bbcf..aeb2e94c 100644
--- a/src/PhpSpreadsheet/Writer/Excel2007/ContentTypes.php
+++ b/src/PhpSpreadsheet/Writer/Excel2007/ContentTypes.php
@@ -146,7 +146,7 @@ class ContentTypes extends WriterPart
                 $mimeType = $this->getParentWriter()->getDrawingHashTable()->getByIndex($i)->getMimeType();
             }
 
-            if (!isset( $aMediaContentTypes[$extension])) {
+            if (!isset($aMediaContentTypes[$extension])) {
                 $aMediaContentTypes[$extension] = $mimeType;
 
                 $this->writeDefaultContentType($objWriter, $extension, $mimeType);
@@ -165,7 +165,7 @@ class ContentTypes extends WriterPart
         for ($i = 0; $i < $sheetCount; ++$i) {
             if (count($pPHPExcel->getSheet()->getHeaderFooter()->getImages()) > 0) {
                 foreach ($pPHPExcel->getSheet()->getHeaderFooter()->getImages() as $image) {
-                    if (!isset( $aMediaContentTypes[strtolower($image->getExtension())])) {
+                    if (!isset($aMediaContentTypes[strtolower($image->getExtension())])) {
                         $aMediaContentTypes[strtolower($image->getExtension())] = $this->getImageMimeType($image->getPath());
 
                         $this->writeDefaultContentType($objWriter, strtolower($image->getExtension()), $aMediaContentTypes[strtolower($image->getExtension())]);
diff --git a/src/PhpSpreadsheet/Writer/Excel2007/Theme.php b/src/PhpSpreadsheet/Writer/Excel2007/Theme.php
index 433f8d64..336edfd2 100644
--- a/src/PhpSpreadsheet/Writer/Excel2007/Theme.php
+++ b/src/PhpSpreadsheet/Writer/Excel2007/Theme.php
@@ -1,5 +1,7 @@
 <?php
+
 namespace PHPExcel\Writer\Excel2007;
+
 /**
  * PHPExcel
  *
diff --git a/src/PhpSpreadsheet/Writer/Excel2007/Worksheet.php b/src/PhpSpreadsheet/Writer/Excel2007/Worksheet.php
index ae50fd26..2eacf606 100644
--- a/src/PhpSpreadsheet/Writer/Excel2007/Worksheet.php
+++ b/src/PhpSpreadsheet/Writer/Excel2007/Worksheet.php
@@ -1,5 +1,6 @@
 <?php
 namespace PHPExcel\Writer\Excel2007;
+
 /**
  * PHPExcel
  *
diff --git a/src/PhpSpreadsheet/Writer/Excel5/Worksheet.php b/src/PhpSpreadsheet/Writer/Excel5/Worksheet.php
index 81d9555a..86b070de 100644
--- a/src/PhpSpreadsheet/Writer/Excel5/Worksheet.php
+++ b/src/PhpSpreadsheet/Writer/Excel5/Worksheet.php
@@ -3233,7 +3233,8 @@ class Worksheet extends BIFFwriter
                     $dataBlockFont .= pack('C', 0x21);
                     $fontUnderline = 0;
                     break;
-                default: $dataBlockFont .= pack('C', 0x00);
+                default:
+                    $dataBlockFont .= pack('C', 0x00);
                     $fontUnderline = 1;
                     break;
             }
diff --git a/src/PhpSpreadsheet/Writer/HTML.php b/src/PhpSpreadsheet/Writer/HTML.php
index 1b15d915..5d82885b 100644
--- a/src/PhpSpreadsheet/Writer/HTML.php
+++ b/src/PhpSpreadsheet/Writer/HTML.php
@@ -1,5 +1,7 @@
 <?php
 
+namespace PHPExcel\Writer;
+
 /**
  * PHPExcel_Writer_HTML
  *
@@ -25,7 +27,7 @@
  * @license    http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt    LGPL
  * @version    ##VERSION##, ##DATE##
  */
-class PHPExcel_Writer_HTML extends PHPExcel_Writer_Abstract implements PHPExcel_Writer_IWriter
+class HTML extends BaseWriter implements IWriter
 {
     /**
      * PHPExcel object
diff --git a/src/PhpSpreadsheet/Writer/OpenDocument.php b/src/PhpSpreadsheet/Writer/OpenDocument.php
index 7b2e04f3..4c867177 100644
--- a/src/PhpSpreadsheet/Writer/OpenDocument.php
+++ b/src/PhpSpreadsheet/Writer/OpenDocument.php
@@ -1,5 +1,7 @@
 <?php
 
+namespace PHPExcel\Writer;
+
 /**
  * PHPExcel_Writer_OpenDocument
  *
@@ -25,7 +27,7 @@
  * @license    http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt    LGPL
  * @version    ##VERSION##, ##DATE##
  */
-class PHPExcel_Writer_OpenDocument extends PHPExcel_Writer_Abstract implements PHPExcel_Writer_IWriter
+class OpenDocument extends BaseWriter implements IWriter
 {
     /**
      * Private writer parts
diff --git a/src/PhpSpreadsheet/Writer/OpenDocument/Cell/Comment.php b/src/PhpSpreadsheet/Writer/OpenDocument/Cell/Comment.php
index f1e98a16..f284de46 100644
--- a/src/PhpSpreadsheet/Writer/OpenDocument/Cell/Comment.php
+++ b/src/PhpSpreadsheet/Writer/OpenDocument/Cell/Comment.php
@@ -1,4 +1,7 @@
 <?php
+
+namespace PHPExcel\Writer\OpenDocument\Cell;
+
 /**
  * PHPExcel
  *
@@ -34,7 +37,7 @@
  * @copyright  Copyright (c) 2006 - 2015 PHPExcel (http://www.codeplex.com/PHPExcel)
  * @author     Alexander Pervakov <frost-nzcr4@jagmort.com>
  */
-class PHPExcel_Writer_OpenDocument_Cell_Comment
+class Comment
 {
     public static function write(PHPExcel_Shared_XMLWriter $objWriter, PHPExcel_Cell $cell)
     {
diff --git a/src/PhpSpreadsheet/Writer/OpenDocument/Content.php b/src/PhpSpreadsheet/Writer/OpenDocument/Content.php
index b2991673..9cb2ecda 100644
--- a/src/PhpSpreadsheet/Writer/OpenDocument/Content.php
+++ b/src/PhpSpreadsheet/Writer/OpenDocument/Content.php
@@ -1,4 +1,7 @@
 <?php
+
+namespace PHPExcel\Writer\OpenDocument;
+
 /**
  * PHPExcel
  *
@@ -34,7 +37,7 @@
  * @copyright  Copyright (c) 2006 - 2015 PHPExcel (http://www.codeplex.com/PHPExcel)
  * @author     Alexander Pervakov <frost-nzcr4@jagmort.com>
  */
-class PHPExcel_Writer_OpenDocument_Content extends PHPExcel_Writer_OpenDocument_WriterPart
+class Content extends WriterPart
 {
     const NUMBER_COLS_REPEATED_MAX = 1024;
     const NUMBER_ROWS_REPEATED_MAX = 1048576;
diff --git a/src/PhpSpreadsheet/Writer/OpenDocument/Meta.php b/src/PhpSpreadsheet/Writer/OpenDocument/Meta.php
index 51f07c97..3b344b83 100644
--- a/src/PhpSpreadsheet/Writer/OpenDocument/Meta.php
+++ b/src/PhpSpreadsheet/Writer/OpenDocument/Meta.php
@@ -1,5 +1,7 @@
 <?php
 
+namespace PHPExcel\Writer\OpenDocument;
+
 /**
  * PHPExcel_Writer_OpenDocument_Meta
  *
@@ -25,7 +27,7 @@
  * @license    http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt    LGPL
  * @version    ##VERSION##, ##DATE##
  */
-class PHPExcel_Writer_OpenDocument_Meta extends PHPExcel_Writer_OpenDocument_WriterPart
+class Meta extends WriterPart
 {
     /**
      * Write meta.xml to XML format
diff --git a/src/PhpSpreadsheet/Writer/OpenDocument/MetaInf.php b/src/PhpSpreadsheet/Writer/OpenDocument/MetaInf.php
index 652a6bc8..d89cd7c7 100644
--- a/src/PhpSpreadsheet/Writer/OpenDocument/MetaInf.php
+++ b/src/PhpSpreadsheet/Writer/OpenDocument/MetaInf.php
@@ -1,5 +1,7 @@
 <?php
 
+namespace PHPExcel\Writer\OpenDocument;
+
 /**
  * PHPExcel_Writer_OpenDocument_MetaInf
  *
@@ -25,7 +27,7 @@
  * @license    http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt    LGPL
  * @version    ##VERSION##, ##DATE##
  */
-class PHPExcel_Writer_OpenDocument_MetaInf extends PHPExcel_Writer_OpenDocument_WriterPart
+class MetaInf extends WriterPart
 {
     /**
      * Write META-INF/manifest.xml to XML format
diff --git a/src/PhpSpreadsheet/Writer/OpenDocument/Mimetype.php b/src/PhpSpreadsheet/Writer/OpenDocument/Mimetype.php
index 783db493..cb58ae1b 100644
--- a/src/PhpSpreadsheet/Writer/OpenDocument/Mimetype.php
+++ b/src/PhpSpreadsheet/Writer/OpenDocument/Mimetype.php
@@ -1,5 +1,7 @@
 <?php
 
+namespace PHPExcel\Writer\OpenDocument;
+
 /**
  * PHPExcel
  *
@@ -25,7 +27,7 @@
  * @license    http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt    LGPL
  * @version    ##VERSION##, ##DATE##
  */
-class PHPExcel_Writer_OpenDocument_Mimetype extends PHPExcel_Writer_OpenDocument_WriterPart
+class Mimetype extends WriterPart
 {
     /**
      * Write mimetype to plain text format
diff --git a/src/PhpSpreadsheet/Writer/OpenDocument/Settings.php b/src/PhpSpreadsheet/Writer/OpenDocument/Settings.php
index 7a22186c..b0b2d458 100644
--- a/src/PhpSpreadsheet/Writer/OpenDocument/Settings.php
+++ b/src/PhpSpreadsheet/Writer/OpenDocument/Settings.php
@@ -1,5 +1,7 @@
 <?php
 
+namespace PHPExcel\Writer\OpenDocument;
+
 /**
  * PHPExcel_Writer_OpenDocument_Settings
  *
@@ -25,7 +27,7 @@
  * @license    http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt    LGPL
  * @version    ##VERSION##, ##DATE##
  */
-class PHPExcel_Writer_OpenDocument_Settings extends PHPExcel_Writer_OpenDocument_WriterPart
+class Settings extends WriterPart
 {
     /**
      * Write settings.xml to XML format
diff --git a/src/PhpSpreadsheet/Writer/OpenDocument/Styles.php b/src/PhpSpreadsheet/Writer/OpenDocument/Styles.php
index 76d120dd..1287b458 100644
--- a/src/PhpSpreadsheet/Writer/OpenDocument/Styles.php
+++ b/src/PhpSpreadsheet/Writer/OpenDocument/Styles.php
@@ -1,5 +1,7 @@
 <?php
 
+namespace PHPExcel\Writer\OpenDocument;
+
 /**
  * PHPExcel_Writer_OpenDocument_Styles
  *
@@ -25,7 +27,7 @@
  * @license    http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt    LGPL
  * @version    ##VERSION##, ##DATE##
  */
-class PHPExcel_Writer_OpenDocument_Styles extends PHPExcel_Writer_OpenDocument_WriterPart
+class Styles extends WriterPart
 {
     /**
      * Write styles.xml to XML format
diff --git a/src/PhpSpreadsheet/Writer/OpenDocument/Thumbnails.php b/src/PhpSpreadsheet/Writer/OpenDocument/Thumbnails.php
index b59c37d4..73aa6189 100644
--- a/src/PhpSpreadsheet/Writer/OpenDocument/Thumbnails.php
+++ b/src/PhpSpreadsheet/Writer/OpenDocument/Thumbnails.php
@@ -1,5 +1,7 @@
 <?php
 
+namespace PHPExcel\Writer\OpenDocument;
+
 /**
  * PHPExcel_Writer_OpenDocument_Thumbnails
  *
@@ -25,7 +27,7 @@
  * @license    http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt    LGPL
  * @version    ##VERSION##, ##DATE##
  */
-class PHPExcel_Writer_OpenDocument_Thumbnails extends PHPExcel_Writer_OpenDocument_WriterPart
+class Thumbnails extends WriterPart
 {
     /**
      * Write Thumbnails/thumbnail.png to PNG format
diff --git a/src/PhpSpreadsheet/Writer/OpenDocument/WriterPart.php b/src/PhpSpreadsheet/Writer/OpenDocument/WriterPart.php
index d1e2ac48..464ec6d2 100644
--- a/src/PhpSpreadsheet/Writer/OpenDocument/WriterPart.php
+++ b/src/PhpSpreadsheet/Writer/OpenDocument/WriterPart.php
@@ -1,5 +1,7 @@
 <?php
 
+namespace PHPExcel\Writer\OpenDocument;
+
 /**
  * PHPExcel_Writer_OpenDocument_WriterPart
  *
@@ -25,6 +27,6 @@
  * @license    http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt    LGPL
  * @version    ##VERSION##, ##DATE##
  */
-abstract class PHPExcel_Writer_OpenDocument_WriterPart extends \PHPExcel\Writer\Excel2007\WriterPart
+abstract class WriterPart extends \PHPExcel\Writer\Excel2007\WriterPart
 {
 }