diff --git a/Classes/PHPExcel/Writer/Abstract.php b/Classes/PHPExcel/Writer/Abstract.php
index fca6a60cc..6181f79f3 100644
--- a/Classes/PHPExcel/Writer/Abstract.php
+++ b/Classes/PHPExcel/Writer/Abstract.php
@@ -66,6 +66,13 @@ abstract class PHPExcel_Writer_Abstract implements PHPExcel_Writer_IWriter
 	 */
 	protected $_diskCachingDirectory	= './';
 
+    /**
+     * PHPExcel instance
+     *
+     * @var PHPExcel
+     */
+    protected $_phpExcel;
+
 	/**
 	 * Write charts in workbook?
 	 *		If this is true, then the Writer will write definitions for any charts that exist in the PHPExcel object.
@@ -155,4 +162,32 @@ public function setUseDiskCaching($pValue = FALSE, $pDirectory = NULL) {
 	public function getDiskCachingDirectory() {
 		return $this->_diskCachingDirectory;
 	}
+
+    /**
+     * Get PHPExcel object
+     *
+     * @return PHPExcel
+     * @throws PHPExcel_Writer_Exception
+     */
+    public function getPHPExcel()
+    {
+        if ($this->_phpExcel !== null) {
+            return $this->_phpExcel;
+        } else {
+            throw new PHPExcel_Writer_Exception('No PHPExcel assigned.');
+        }
+    }
+
+    /**
+     * Set PHPExcel object
+     *
+     * @param  PHPExcel  $pPHPExcel  PHPExcel object
+     * @throws PHPExcel_Writer_Exception
+     * @return PHPExcel_Writer_IWriter
+     */
+    public function setPHPExcel(PHPExcel $pPHPExcel = null)
+    {
+        $this->_phpExcel = $pPHPExcel;
+        return $this;
+    }
 }
diff --git a/Classes/PHPExcel/Writer/CSV.php b/Classes/PHPExcel/Writer/CSV.php
index 97961ccca..1a2f2b4dc 100644
--- a/Classes/PHPExcel/Writer/CSV.php
+++ b/Classes/PHPExcel/Writer/CSV.php
@@ -33,14 +33,8 @@
  * @package	PHPExcel_Writer_CSV
  * @copyright  Copyright (c) 2006 - 2014 PHPExcel (http://www.codeplex.com/PHPExcel)
  */
-class PHPExcel_Writer_CSV extends PHPExcel_Writer_Abstract implements PHPExcel_Writer_IWriter {
-	/**
-	 * PHPExcel object
-	 *
-	 * @var PHPExcel
-	 */
-	private $_phpExcel;
-
+class PHPExcel_Writer_CSV extends PHPExcel_Writer_Abstract
+{
 	/**
 	 * Delimiter
 	 *
@@ -89,7 +83,7 @@ class PHPExcel_Writer_CSV extends PHPExcel_Writer_Abstract implements PHPExcel_W
 	 * @param	PHPExcel	$phpExcel	PHPExcel object
 	 */
 	public function __construct(PHPExcel $phpExcel) {
-		$this->_phpExcel	= $phpExcel;
+		$this->setPHPExcel($phpExcel);
 	}
 
 	/**
@@ -98,7 +92,12 @@ public function __construct(PHPExcel $phpExcel) {
 	 * @param	string		$pFilename
 	 * @throws	PHPExcel_Writer_Exception
 	 */
-	public function save($pFilename = null) {
+	public function save($pFilename = null)
+	{
+        if (!$this->_phpExcel) {
+            throw new PHPExcel_Writer_Exception('PHPExcel object unassigned.');
+        }
+
 		// Fetch sheet
 		$sheet = $this->_phpExcel->getSheet($this->_sheetIndex);
 
diff --git a/Classes/PHPExcel/Writer/Excel2007.php b/Classes/PHPExcel/Writer/Excel2007.php
index 4cf14ac1c..996fdafdf 100644
--- a/Classes/PHPExcel/Writer/Excel2007.php
+++ b/Classes/PHPExcel/Writer/Excel2007.php
@@ -33,7 +33,7 @@
  * @package    PHPExcel_Writer_2007
  * @copyright  Copyright (c) 2006 - 2014 PHPExcel (http://www.codeplex.com/PHPExcel)
  */
-class PHPExcel_Writer_Excel2007 extends PHPExcel_Writer_Abstract implements PHPExcel_Writer_IWriter
+class PHPExcel_Writer_Excel2007 extends PHPExcel_Writer_Abstract
 {
 	/**
 	 * Pre-calculate formulas
@@ -60,13 +60,6 @@ class PHPExcel_Writer_Excel2007 extends PHPExcel_Writer_Abstract implements PHPE
 	 */
 	private $_writerParts	= array();
 
-	/**
-	 * Private PHPExcel
-	 *
-	 * @var PHPExcel
-	 */
-	private $_spreadSheet;
-
 	/**
 	 * Private string table
 	 *
@@ -187,9 +180,9 @@ public function getWriterPart($pPartName = '') {
 	 */
 	public function save($pFilename = null)
 	{
-		if ($this->_spreadSheet !== NULL) {
+		if ($this->_phpExcel !== NULL) {
 			// garbage collect
-			$this->_spreadSheet->garbageCollect();
+			$this->_phpExcel->garbageCollect();
 
 			// If $pFilename is php://output or php://stdout, make it a temporary file...
 			$originalFilename = $pFilename;
@@ -200,27 +193,27 @@ public function save($pFilename = null)
 				}
 			}
 
-			$saveDebugLog = PHPExcel_Calculation::getInstance($this->_spreadSheet)->getDebugLog()->getWriteDebugLog();
-			PHPExcel_Calculation::getInstance($this->_spreadSheet)->getDebugLog()->setWriteDebugLog(FALSE);
+			$saveDebugLog = PHPExcel_Calculation::getInstance($this->_phpExcel)->getDebugLog()->getWriteDebugLog();
+			PHPExcel_Calculation::getInstance($this->_phpExcel)->getDebugLog()->setWriteDebugLog(FALSE);
 			$saveDateReturnType = PHPExcel_Calculation_Functions::getReturnDateType();
 			PHPExcel_Calculation_Functions::setReturnDateType(PHPExcel_Calculation_Functions::RETURNDATE_EXCEL);
 
 			// Create string lookup table
 			$this->_stringTable = array();
-			for ($i = 0; $i < $this->_spreadSheet->getSheetCount(); ++$i) {
-				$this->_stringTable = $this->getWriterPart('StringTable')->createStringTable($this->_spreadSheet->getSheet($i), $this->_stringTable);
+			for ($i = 0; $i < $this->_phpExcel->getSheetCount(); ++$i) {
+				$this->_stringTable = $this->getWriterPart('StringTable')->createStringTable($this->_phpExcel->getSheet($i), $this->_stringTable);
 			}
 
 			// Create styles dictionaries
-			$this->_styleHashTable->addFromSource( 	            $this->getWriterPart('Style')->allStyles($this->_spreadSheet) 			);
-			$this->_stylesConditionalHashTable->addFromSource( 	$this->getWriterPart('Style')->allConditionalStyles($this->_spreadSheet) 			);
-			$this->_fillHashTable->addFromSource( 				$this->getWriterPart('Style')->allFills($this->_spreadSheet) 			);
-			$this->_fontHashTable->addFromSource( 				$this->getWriterPart('Style')->allFonts($this->_spreadSheet) 			);
-			$this->_bordersHashTable->addFromSource( 			$this->getWriterPart('Style')->allBorders($this->_spreadSheet) 			);
-			$this->_numFmtHashTable->addFromSource( 			$this->getWriterPart('Style')->allNumberFormats($this->_spreadSheet) 	);
+			$this->_styleHashTable->addFromSource( 	            $this->getWriterPart('Style')->allStyles($this->_phpExcel) 			);
+			$this->_stylesConditionalHashTable->addFromSource( 	$this->getWriterPart('Style')->allConditionalStyles($this->_phpExcel) 			);
+			$this->_fillHashTable->addFromSource( 				$this->getWriterPart('Style')->allFills($this->_phpExcel) 			);
+			$this->_fontHashTable->addFromSource( 				$this->getWriterPart('Style')->allFonts($this->_phpExcel) 			);
+			$this->_bordersHashTable->addFromSource( 			$this->getWriterPart('Style')->allBorders($this->_phpExcel) 			);
+			$this->_numFmtHashTable->addFromSource( 			$this->getWriterPart('Style')->allNumberFormats($this->_phpExcel) 	);
 
 			// Create drawing dictionary
-			$this->_drawingHashTable->addFromSource( 			$this->getWriterPart('Drawing')->allDrawings($this->_spreadSheet) 		);
+			$this->_drawingHashTable->addFromSource( 			$this->getWriterPart('Drawing')->allDrawings($this->_phpExcel) 		);
 
 			// Create new ZIP file and open it for writing
 			$zipClass = PHPExcel_Settings::getZipClass();
@@ -243,67 +236,67 @@ public function save($pFilename = null)
 			}
 
 			// Add [Content_Types].xml to ZIP file
-			$objZip->addFromString('[Content_Types].xml', 			$this->getWriterPart('ContentTypes')->writeContentTypes($this->_spreadSheet, $this->_includeCharts));
+			$objZip->addFromString('[Content_Types].xml', 			$this->getWriterPart('ContentTypes')->writeContentTypes($this->_phpExcel, $this->_includeCharts));
 
 			//if hasMacros, add the vbaProject.bin file, Certificate file(if exists)
-			if($this->_spreadSheet->hasMacros()){
-				$macrosCode=$this->_spreadSheet->getMacrosCode();
+			if($this->_phpExcel->hasMacros()){
+				$macrosCode=$this->_phpExcel->getMacrosCode();
 				if(!is_null($macrosCode)){// we have the code ?
 					$objZip->addFromString('xl/vbaProject.bin', $macrosCode);//allways in 'xl', allways named vbaProject.bin
-					if($this->_spreadSheet->hasMacrosCertificate()){//signed macros ?
+					if($this->_phpExcel->hasMacrosCertificate()){//signed macros ?
 						// Yes : add the certificate file and the related rels file
-						$objZip->addFromString('xl/vbaProjectSignature.bin', $this->_spreadSheet->getMacrosCertificate());
+						$objZip->addFromString('xl/vbaProjectSignature.bin', $this->_phpExcel->getMacrosCertificate());
 						$objZip->addFromString('xl/_rels/vbaProject.bin.rels',
-							$this->getWriterPart('RelsVBA')->writeVBARelationships($this->_spreadSheet));
+							$this->getWriterPart('RelsVBA')->writeVBARelationships($this->_phpExcel));
 					}
 				}
 			}
 			//a custom UI in this workbook ? add it ("base" xml and additional objects (pictures) and rels)
-			if($this->_spreadSheet->hasRibbon()){
-				$tmpRibbonTarget=$this->_spreadSheet->getRibbonXMLData('target');
-				$objZip->addFromString($tmpRibbonTarget, $this->_spreadSheet->getRibbonXMLData('data'));
-				if($this->_spreadSheet->hasRibbonBinObjects()){
+			if($this->_phpExcel->hasRibbon()){
+				$tmpRibbonTarget=$this->_phpExcel->getRibbonXMLData('target');
+				$objZip->addFromString($tmpRibbonTarget, $this->_phpExcel->getRibbonXMLData('data'));
+				if($this->_phpExcel->hasRibbonBinObjects()){
 					$tmpRootPath=dirname($tmpRibbonTarget).'/';
-					$ribbonBinObjects=$this->_spreadSheet->getRibbonBinObjects('data');//the files to write
+					$ribbonBinObjects=$this->_phpExcel->getRibbonBinObjects('data');//the files to write
 					foreach($ribbonBinObjects as $aPath=>$aContent){
 						$objZip->addFromString($tmpRootPath.$aPath, $aContent);
 					}
 					//the rels for files
 					$objZip->addFromString($tmpRootPath.'_rels/'.basename($tmpRibbonTarget).'.rels',
-						$this->getWriterPart('RelsRibbonObjects')->writeRibbonRelationships($this->_spreadSheet));
+						$this->getWriterPart('RelsRibbonObjects')->writeRibbonRelationships($this->_phpExcel));
 				}
 			}
-			
+
 			// Add relationships to ZIP file
-			$objZip->addFromString('_rels/.rels', 					$this->getWriterPart('Rels')->writeRelationships($this->_spreadSheet));
-			$objZip->addFromString('xl/_rels/workbook.xml.rels', 	$this->getWriterPart('Rels')->writeWorkbookRelationships($this->_spreadSheet));
+			$objZip->addFromString('_rels/.rels', 					$this->getWriterPart('Rels')->writeRelationships($this->_phpExcel));
+			$objZip->addFromString('xl/_rels/workbook.xml.rels', 	$this->getWriterPart('Rels')->writeWorkbookRelationships($this->_phpExcel));
 
 			// Add document properties to ZIP file
-			$objZip->addFromString('docProps/app.xml', 				$this->getWriterPart('DocProps')->writeDocPropsApp($this->_spreadSheet));
-			$objZip->addFromString('docProps/core.xml', 			$this->getWriterPart('DocProps')->writeDocPropsCore($this->_spreadSheet));
-			$customPropertiesPart = $this->getWriterPart('DocProps')->writeDocPropsCustom($this->_spreadSheet);
+			$objZip->addFromString('docProps/app.xml', 				$this->getWriterPart('DocProps')->writeDocPropsApp($this->_phpExcel));
+			$objZip->addFromString('docProps/core.xml', 			$this->getWriterPart('DocProps')->writeDocPropsCore($this->_phpExcel));
+			$customPropertiesPart = $this->getWriterPart('DocProps')->writeDocPropsCustom($this->_phpExcel);
 			if ($customPropertiesPart !== NULL) {
 				$objZip->addFromString('docProps/custom.xml', 		$customPropertiesPart);
 			}
 
 			// Add theme to ZIP file
-			$objZip->addFromString('xl/theme/theme1.xml', 			$this->getWriterPart('Theme')->writeTheme($this->_spreadSheet));
+			$objZip->addFromString('xl/theme/theme1.xml', 			$this->getWriterPart('Theme')->writeTheme($this->_phpExcel));
 
 			// Add string table to ZIP file
 			$objZip->addFromString('xl/sharedStrings.xml', 			$this->getWriterPart('StringTable')->writeStringTable($this->_stringTable));
 
 			// Add styles to ZIP file
-			$objZip->addFromString('xl/styles.xml', 				$this->getWriterPart('Style')->writeStyles($this->_spreadSheet));
+			$objZip->addFromString('xl/styles.xml', 				$this->getWriterPart('Style')->writeStyles($this->_phpExcel));
 
 			// Add workbook to ZIP file
-			$objZip->addFromString('xl/workbook.xml', 				$this->getWriterPart('Workbook')->writeWorkbook($this->_spreadSheet, $this->_preCalculateFormulas));
+			$objZip->addFromString('xl/workbook.xml', 				$this->getWriterPart('Workbook')->writeWorkbook($this->_phpExcel, $this->_preCalculateFormulas));
 
 			$chartCount = 0;
 			// Add worksheets
-			for ($i = 0; $i < $this->_spreadSheet->getSheetCount(); ++$i) {
-				$objZip->addFromString('xl/worksheets/sheet' . ($i + 1) . '.xml', $this->getWriterPart('Worksheet')->writeWorksheet($this->_spreadSheet->getSheet($i), $this->_stringTable, $this->_includeCharts));
+			for ($i = 0; $i < $this->_phpExcel->getSheetCount(); ++$i) {
+				$objZip->addFromString('xl/worksheets/sheet' . ($i + 1) . '.xml', $this->getWriterPart('Worksheet')->writeWorksheet($this->_phpExcel->getSheet($i), $this->_stringTable, $this->_includeCharts));
 				if ($this->_includeCharts) {
-					$charts = $this->_spreadSheet->getSheet($i)->getChartCollection();
+					$charts = $this->_phpExcel->getSheet($i)->getChartCollection();
 					if (count($charts) > 0) {
 						foreach($charts as $chart) {
 							$objZip->addFromString('xl/charts/chart' . ($chartCount + 1) . '.xml', $this->getWriterPart('Chart')->writeChart($chart));
@@ -315,45 +308,45 @@ public function save($pFilename = null)
 
 			$chartRef1 = $chartRef2 = 0;
 			// Add worksheet relationships (drawings, ...)
-			for ($i = 0; $i < $this->_spreadSheet->getSheetCount(); ++$i) {
+			for ($i = 0; $i < $this->_phpExcel->getSheetCount(); ++$i) {
 
 				// Add relationships
-				$objZip->addFromString('xl/worksheets/_rels/sheet' . ($i + 1) . '.xml.rels', 	$this->getWriterPart('Rels')->writeWorksheetRelationships($this->_spreadSheet->getSheet($i), ($i + 1), $this->_includeCharts));
+				$objZip->addFromString('xl/worksheets/_rels/sheet' . ($i + 1) . '.xml.rels', 	$this->getWriterPart('Rels')->writeWorksheetRelationships($this->_phpExcel->getSheet($i), ($i + 1), $this->_includeCharts));
 
-				$drawings = $this->_spreadSheet->getSheet($i)->getDrawingCollection();
+				$drawings = $this->_phpExcel->getSheet($i)->getDrawingCollection();
 				$drawingCount = count($drawings);
 				if ($this->_includeCharts) {
-					$chartCount = $this->_spreadSheet->getSheet($i)->getChartCount();
+					$chartCount = $this->_phpExcel->getSheet($i)->getChartCount();
 				}
 
 				// Add drawing and image relationship parts
 				if (($drawingCount > 0) || ($chartCount > 0)) {
 					// Drawing relationships
-					$objZip->addFromString('xl/drawings/_rels/drawing' . ($i + 1) . '.xml.rels', $this->getWriterPart('Rels')->writeDrawingRelationships($this->_spreadSheet->getSheet($i),$chartRef1, $this->_includeCharts));
+					$objZip->addFromString('xl/drawings/_rels/drawing' . ($i + 1) . '.xml.rels', $this->getWriterPart('Rels')->writeDrawingRelationships($this->_phpExcel->getSheet($i),$chartRef1, $this->_includeCharts));
 
 					// Drawings
-					$objZip->addFromString('xl/drawings/drawing' . ($i + 1) . '.xml', $this->getWriterPart('Drawing')->writeDrawings($this->_spreadSheet->getSheet($i),$chartRef2,$this->_includeCharts));
+					$objZip->addFromString('xl/drawings/drawing' . ($i + 1) . '.xml', $this->getWriterPart('Drawing')->writeDrawings($this->_phpExcel->getSheet($i),$chartRef2,$this->_includeCharts));
 				}
 
 				// Add comment relationship parts
-				if (count($this->_spreadSheet->getSheet($i)->getComments()) > 0) {
+				if (count($this->_phpExcel->getSheet($i)->getComments()) > 0) {
 					// VML Comments
-					$objZip->addFromString('xl/drawings/vmlDrawing' . ($i + 1) . '.vml', $this->getWriterPart('Comments')->writeVMLComments($this->_spreadSheet->getSheet($i)));
+					$objZip->addFromString('xl/drawings/vmlDrawing' . ($i + 1) . '.vml', $this->getWriterPart('Comments')->writeVMLComments($this->_phpExcel->getSheet($i)));
 
 					// Comments
-					$objZip->addFromString('xl/comments' . ($i + 1) . '.xml', $this->getWriterPart('Comments')->writeComments($this->_spreadSheet->getSheet($i)));
+					$objZip->addFromString('xl/comments' . ($i + 1) . '.xml', $this->getWriterPart('Comments')->writeComments($this->_phpExcel->getSheet($i)));
 				}
 
 				// Add header/footer relationship parts
-				if (count($this->_spreadSheet->getSheet($i)->getHeaderFooter()->getImages()) > 0) {
+				if (count($this->_phpExcel->getSheet($i)->getHeaderFooter()->getImages()) > 0) {
 					// VML Drawings
-					$objZip->addFromString('xl/drawings/vmlDrawingHF' . ($i + 1) . '.vml', $this->getWriterPart('Drawing')->writeVMLHeaderFooterImages($this->_spreadSheet->getSheet($i)));
+					$objZip->addFromString('xl/drawings/vmlDrawingHF' . ($i + 1) . '.vml', $this->getWriterPart('Drawing')->writeVMLHeaderFooterImages($this->_phpExcel->getSheet($i)));
 
 					// VML Drawing relationships
-					$objZip->addFromString('xl/drawings/_rels/vmlDrawingHF' . ($i + 1) . '.vml.rels', $this->getWriterPart('Rels')->writeHeaderFooterDrawingRelationships($this->_spreadSheet->getSheet($i)));
+					$objZip->addFromString('xl/drawings/_rels/vmlDrawingHF' . ($i + 1) . '.vml.rels', $this->getWriterPart('Rels')->writeHeaderFooterDrawingRelationships($this->_phpExcel->getSheet($i)));
 
 					// Media
-					foreach ($this->_spreadSheet->getSheet($i)->getHeaderFooter()->getImages() as $image) {
+					foreach ($this->_phpExcel->getSheet($i)->getHeaderFooter()->getImages() as $image) {
 						$objZip->addFromString('xl/media/' . $image->getIndexedFilename(), file_get_contents($image->getPath()));
 					}
 				}
@@ -392,7 +385,7 @@ public function save($pFilename = null)
 			}
 
 			PHPExcel_Calculation_Functions::setReturnDateType($saveDateReturnType);
-			PHPExcel_Calculation::getInstance($this->_spreadSheet)->getDebugLog()->setWriteDebugLog($saveDebugLog);
+			PHPExcel_Calculation::getInstance($this->_phpExcel)->getDebugLog()->setWriteDebugLog($saveDebugLog);
 
 			// Close file
 			if ($objZip->close() === false) {
@@ -411,32 +404,6 @@ public function save($pFilename = null)
 		}
 	}
 
-	/**
-	 * Get PHPExcel object
-	 *
-	 * @return PHPExcel
-	 * @throws PHPExcel_Writer_Exception
-	 */
-	public function getPHPExcel() {
-		if ($this->_spreadSheet !== null) {
-			return $this->_spreadSheet;
-		} else {
-			throw new PHPExcel_Writer_Exception("No PHPExcel assigned.");
-		}
-	}
-
-	/**
-	 * Set PHPExcel object
-	 *
-	 * @param 	PHPExcel 	$pPHPExcel	PHPExcel object
-	 * @throws	PHPExcel_Writer_Exception
-	 * @return PHPExcel_Writer_Excel2007
-	 */
-	public function setPHPExcel(PHPExcel $pPHPExcel = null) {
-		$this->_spreadSheet = $pPHPExcel;
-		return $this;
-	}
-
     /**
      * Get string table
      *
diff --git a/Classes/PHPExcel/Writer/Excel5.php b/Classes/PHPExcel/Writer/Excel5.php
index 1a990d045..ca93d11b2 100644
--- a/Classes/PHPExcel/Writer/Excel5.php
+++ b/Classes/PHPExcel/Writer/Excel5.php
@@ -33,15 +33,8 @@
  * @package    PHPExcel_Writer_Excel5
  * @copyright  Copyright (c) 2006 - 2014 PHPExcel (http://www.codeplex.com/PHPExcel)
  */
-class PHPExcel_Writer_Excel5 extends PHPExcel_Writer_Abstract implements PHPExcel_Writer_IWriter
+class PHPExcel_Writer_Excel5 extends PHPExcel_Writer_Abstract
 {
-	/**
-	 * PHPExcel object
-	 *
-	 * @var PHPExcel
-	 */
-	private $_phpExcel;
-
 	/**
 	 * Total number of shared strings in workbook
 	 *
@@ -104,7 +97,7 @@ class PHPExcel_Writer_Excel5 extends PHPExcel_Writer_Abstract implements PHPExce
 	 * @param	PHPExcel	$phpExcel	PHPExcel object
 	 */
 	public function __construct(PHPExcel $phpExcel) {
-		$this->_phpExcel	= $phpExcel;
+		$this->setPHPExcel($phpExcel);
 
 		$this->_parser		= new PHPExcel_Writer_Excel5_Parser();
 	}
@@ -115,7 +108,11 @@ public function __construct(PHPExcel $phpExcel) {
 	 * @param	string		$pFilename
 	 * @throws	PHPExcel_Writer_Exception
 	 */
-	public function save($pFilename = null) {
+	public function save($pFilename = null)
+	{
+        if (!$this->_phpExcel) {
+            throw new PHPExcel_Writer_Exception('PHPExcel object unassigned.');
+        }
 
 		// garbage collect
 		$this->_phpExcel->garbageCollect();
diff --git a/Classes/PHPExcel/Writer/HTML.php b/Classes/PHPExcel/Writer/HTML.php
index 72fd81856..1a74c1abf 100644
--- a/Classes/PHPExcel/Writer/HTML.php
+++ b/Classes/PHPExcel/Writer/HTML.php
@@ -33,14 +33,8 @@
  * @package	PHPExcel_Writer_HTML
  * @copyright  Copyright (c) 2006 - 2014 PHPExcel (http://www.codeplex.com/PHPExcel)
  */
-class PHPExcel_Writer_HTML extends PHPExcel_Writer_Abstract implements PHPExcel_Writer_IWriter {
-	/**
-	 * PHPExcel object
-	 *
-	 * @var PHPExcel
-	 */
-	protected $_phpExcel;
-
+class PHPExcel_Writer_HTML extends PHPExcel_Writer_Abstract
+{
 	/**
 	 * Sheet index to write
 	 *
@@ -138,7 +132,7 @@ class PHPExcel_Writer_HTML extends PHPExcel_Writer_Abstract implements PHPExcel_
 	 * @param	PHPExcel	$phpExcel	PHPExcel object
 	 */
 	public function __construct(PHPExcel $phpExcel) {
-		$this->_phpExcel = $phpExcel;
+		$this->setPHPExcel($phpExcel);
 		$this->_defaultFont = $this->_phpExcel->getDefaultStyle()->getFont();
 	}
 
@@ -148,7 +142,12 @@ public function __construct(PHPExcel $phpExcel) {
 	 * @param	string		$pFilename
 	 * @throws	PHPExcel_Writer_Exception
 	 */
-	public function save($pFilename = null) {
+	public function save($pFilename = null)
+    {
+        if (!$this->_phpExcel) {
+            throw new PHPExcel_Writer_Exception('PHPExcel object unassigned.');
+        }
+
 		// garbage collect
 		$this->_phpExcel->garbageCollect();
 
@@ -608,9 +607,9 @@ private function _writeImageInCell(PHPExcel_Worksheet $pSheet, $coordinates) {
 					}
 
 					$html .= '<div style="position: relative;">';
-					$html .= '<img style="position: absolute; z-index: 1; left: ' . 
-                        $drawing->getOffsetX() . 'px; top: ' . $drawing->getOffsetY() . 'px; width: ' . 
-                        $drawing->getWidth() . 'px; height: ' . $drawing->getHeight() . 'px;" src="' . 
+					$html .= '<img style="position: absolute; z-index: 1; left: ' .
+                        $drawing->getOffsetX() . 'px; top: ' . $drawing->getOffsetY() . 'px; width: ' .
+                        $drawing->getWidth() . 'px; height: ' . $drawing->getHeight() . 'px;" src="' .
                         $imageData . '" border="0" />';
 					$html .= '</div>';
 				}
@@ -967,9 +966,9 @@ private function _createCSSStyleBorders(PHPExcel_Style_Borders $pStyle) {
 	private function _createCSSStyleBorder(PHPExcel_Style_Border $pStyle) {
 		// Create CSS
 //		$css = $this->_mapBorderStyle($pStyle->getBorderStyle()) . ' #' . $pStyle->getColor()->getRGB();
-		//	Create CSS - add !important to non-none border styles for merged cells  
-		$borderStyle = $this->_mapBorderStyle($pStyle->getBorderStyle());  
-		$css = $borderStyle . ' #' . $pStyle->getColor()->getRGB() . (($borderStyle == 'none') ? '' : ' !important'); 
+		//	Create CSS - add !important to non-none border styles for merged cells
+		$borderStyle = $this->_mapBorderStyle($pStyle->getBorderStyle());
+		$css = $borderStyle . ' #' . $pStyle->getColor()->getRGB() . (($borderStyle == 'none') ? '' : ' !important');
 
 		// Return
 		return $css;
@@ -1020,7 +1019,7 @@ private function _generateTableHeader($pSheet) {
 		// Construct HTML
 		$html = '';
 		$html .= $this->_setMargins($pSheet);
-			
+
 		if (!$this->_useInlineCss) {
 			$gridlines = $pSheet->getShowGridlines() ? ' gridlines' : '';
 			$html .= '	<table border="0" cellpadding="0" cellspacing="0" id="sheet' . $sheetIndex . '" class="sheet' . $sheetIndex . $gridlines . '">' . PHP_EOL;
@@ -1528,5 +1527,4 @@ private function _setMargins(PHPExcel_Worksheet $pSheet) {
 
 		return "<style>\n" . $htmlPage . $htmlBody . "</style>\n";
 	}
-	
 }
diff --git a/Classes/PHPExcel/Writer/IWriter.php b/Classes/PHPExcel/Writer/IWriter.php
index f0b94b9e9..d3b828b11 100644
--- a/Classes/PHPExcel/Writer/IWriter.php
+++ b/Classes/PHPExcel/Writer/IWriter.php
@@ -43,4 +43,20 @@ interface PHPExcel_Writer_IWriter
      */
     public function save($pFilename = NULL);
 
+    /**
+     * Get PHPExcel object
+     *
+     * @return PHPExcel
+     * @throws PHPExcel_Writer_Exception
+     */
+    public function getPHPExcel();
+
+    /**
+     * Set PHPExcel object
+     *
+     * @param 	PHPExcel 	$pPHPExcel	PHPExcel object
+     * @throws	PHPExcel_Writer_Exception
+     * @return PHPExcel_Writer_IWriter
+     */
+    public function setPHPExcel(PHPExcel $pPHPExcel = null);
 }
diff --git a/Classes/PHPExcel/Writer/OpenDocument.php b/Classes/PHPExcel/Writer/OpenDocument.php
index 2cbe6f904..532a7568a 100644
--- a/Classes/PHPExcel/Writer/OpenDocument.php
+++ b/Classes/PHPExcel/Writer/OpenDocument.php
@@ -35,7 +35,7 @@
  * @author     Alexander Pervakov <frost-nzcr4@jagmort.com>
  * @link       http://docs.oasis-open.org/office/v1.2/os/OpenDocument-v1.2-os.html
  */
-class PHPExcel_Writer_OpenDocument extends PHPExcel_Writer_Abstract implements PHPExcel_Writer_IWriter
+class PHPExcel_Writer_OpenDocument extends PHPExcel_Writer_Abstract
 {
     /**
      * Private writer parts
@@ -44,13 +44,6 @@ class PHPExcel_Writer_OpenDocument extends PHPExcel_Writer_Abstract implements P
      */
     private $_writerParts = array();
 
-    /**
-     * Private PHPExcel
-     *
-     * @var PHPExcel
-     */
-    private $_spreadSheet;
-
     /**
      * Create a new PHPExcel_Writer_OpenDocument
      *
@@ -98,12 +91,12 @@ public function getWriterPart($pPartName = '')
      */
     public function save($pFilename = NULL)
     {
-        if (!$this->_spreadSheet) {
+        if (!$this->_phpExcel) {
             throw new PHPExcel_Writer_Exception('PHPExcel object unassigned.');
         }
 
         // garbage collect
-        $this->_spreadSheet->garbageCollect();
+        $this->_phpExcel->garbageCollect();
 
         // If $pFilename is php://output or php://stdout, make it a temporary file...
         $originalFilename = $pFilename;
@@ -169,32 +162,4 @@ private function _createZip($pFilename)
 
         return $objZip;
     }
-
-    /**
-     * Get PHPExcel object
-     *
-     * @return PHPExcel
-     * @throws PHPExcel_Writer_Exception
-     */
-    public function getPHPExcel()
-    {
-        if ($this->_spreadSheet !== null) {
-            return $this->_spreadSheet;
-        } else {
-            throw new PHPExcel_Writer_Exception('No PHPExcel assigned.');
-        }
-    }
-
-    /**
-     * Set PHPExcel object
-     *
-     * @param  PHPExcel  $pPHPExcel  PHPExcel object
-     * @throws PHPExcel_Writer_Exception
-     * @return PHPExcel_Writer_Excel2007
-     */
-    public function setPHPExcel(PHPExcel $pPHPExcel = null)
-    {
-        $this->_spreadSheet = $pPHPExcel;
-        return $this;
-    }
 }
diff --git a/Classes/PHPExcel/Writer/PDF/DomPDF.php b/Classes/PHPExcel/Writer/PDF/DomPDF.php
index 01e4e0122..de39afa0a 100644
--- a/Classes/PHPExcel/Writer/PDF/DomPDF.php
+++ b/Classes/PHPExcel/Writer/PDF/DomPDF.php
@@ -61,6 +61,10 @@ public function __construct(PHPExcel $phpExcel)
      */
     public function save($pFilename = NULL)
     {
+        if (!$this->_phpExcel) {
+            throw new PHPExcel_Writer_Exception('PHPExcel object unassigned.');
+        }
+
         $fileHandle = parent::prepareForSave($pFilename);
 
         //  Default PDF paper size
@@ -83,7 +87,7 @@ public function save($pFilename = NULL)
             $printMargins = $this->_phpExcel->getSheet($this->getSheetIndex())->getPageMargins();
         }
 
-        
+
         $orientation = ($orientation == 'L') ? 'landscape' : 'portrait';
 
         //  Override Page Orientation
diff --git a/Classes/PHPExcel/Writer/PDF/mPDF.php b/Classes/PHPExcel/Writer/PDF/mPDF.php
index dddc097d3..bd01e70b8 100644
--- a/Classes/PHPExcel/Writer/PDF/mPDF.php
+++ b/Classes/PHPExcel/Writer/PDF/mPDF.php
@@ -61,6 +61,10 @@ public function __construct(PHPExcel $phpExcel)
      */
     public function save($pFilename = NULL)
     {
+        if (!$this->_phpExcel) {
+            throw new PHPExcel_Writer_Exception('PHPExcel object unassigned.');
+        }
+
         $fileHandle = parent::prepareForSave($pFilename);
 
         //  Default PDF paper size
diff --git a/Classes/PHPExcel/Writer/PDF/tcPDF.php b/Classes/PHPExcel/Writer/PDF/tcPDF.php
index 4e1937afc..06deaf971 100644
--- a/Classes/PHPExcel/Writer/PDF/tcPDF.php
+++ b/Classes/PHPExcel/Writer/PDF/tcPDF.php
@@ -62,6 +62,10 @@ public function __construct(PHPExcel $phpExcel)
      */
     public function save($pFilename = NULL)
     {
+        if (!$this->_phpExcel) {
+            throw new PHPExcel_Writer_Exception('PHPExcel object unassigned.');
+        }
+
         $fileHandle = parent::prepareForSave($pFilename);
 
         //  Default PDF paper size