diff --git a/src/PhpSpreadsheet/Calculation.php b/src/PhpSpreadsheet/Calculation.php
index 32577143..d649d23b 100644
--- a/src/PhpSpreadsheet/Calculation.php
+++ b/src/PhpSpreadsheet/Calculation.php
@@ -2102,7 +2102,7 @@ class Calculation
      * Get an instance of this class
      *
      * @access    public
-     * @param   PHPExcel $spreadsheet  Injected spreadsheet for working with a PHPExcel object,
+     * @param   Spreadsheet $spreadsheet  Injected spreadsheet for working with a PHPExcel Spreadsheet object,
      *                                    or NULL to create a standalone claculation engine
      * @return Calculation
      */
@@ -2126,9 +2126,9 @@ class Calculation
      * Unset an instance of this class
      *
      * @access    public
-     * @param   PHPExcel $spreadsheet  Injected spreadsheet identifying the instance to unset
+     * @param   Spreadsheet $spreadsheet  Injected spreadsheet identifying the instance to unset
      */
-    public static function unsetInstance(PHPExcel $spreadsheet = null)
+    public static function unsetInstance(Spreadsheet $spreadsheet = null)
     {
         if ($spreadsheet !== null) {
             if (isset(self::$spreadsheetSets[$spreadsheet->getID()])) {
diff --git a/src/PhpSpreadsheet/Calculation/Categories.php b/src/PhpSpreadsheet/Calculation/Categories.php
index 57766207..8fe2b4db 100644
--- a/src/PhpSpreadsheet/Calculation/Categories.php
+++ b/src/PhpSpreadsheet/Calculation/Categories.php
@@ -50,14 +50,14 @@ class Categories
     private $category;
 
     /**
-     * Excel name
+     * Excel function name
      *
      * @var string
      */
     private $excelName;
 
     /**
-     * PHPExcel name
+     * PHPExcel function name
      *
      * @var string
      */
@@ -67,7 +67,7 @@ class Categories
      * Create a new Categories
      * @param     string        $pCategory         Category (represented by CATEGORY_*)
      * @param     string        $pExcelName        Excel function name
-     * @param     string        $pPHPExcelName    PHPExcel function mapping
+     * @param     string        $pPHPExcelName     PHPExcel internal function name
      * @throws    Exception
      */
     public function __construct($pCategory = null, $pExcelName = null, $pPHPExcelName = null)
@@ -108,7 +108,7 @@ class Categories
     }
 
     /**
-     * Get Excel name
+     * Get Excel function name
      *
      * @return string
      */
@@ -118,7 +118,7 @@ class Categories
     }
 
     /**
-     * Set Excel name
+     * Set Excel function name
      *
      * @param string    $value
      */
@@ -128,7 +128,7 @@ class Categories
     }
 
     /**
-     * Get PHPExcel name
+     * Get PHPExcel function name
      *
      * @return string
      */
@@ -138,7 +138,7 @@ class Categories
     }
 
     /**
-     * Set PHPExcel name
+     * Set PHPExcel function  name
      *
      * @param string    $value
      */
diff --git a/src/PhpSpreadsheet/Calculation/DateTime.php b/src/PhpSpreadsheet/Calculation/DateTime.php
index c2d38600..291a982a 100644
--- a/src/PhpSpreadsheet/Calculation/DateTime.php
+++ b/src/PhpSpreadsheet/Calculation/DateTime.php
@@ -430,7 +430,7 @@ class DateTime
             case Functions::RETURNDATE_EXCEL:
                 $date = 0;
                 $calendar = \PHPExcel\Shared\Date::getExcelCalendar();
-                if ($calendar != PHPExcel\Shared\Date::CALENDAR_WINDOWS_1900) {
+                if ($calendar != \PHPExcel\Shared\Date::CALENDAR_WINDOWS_1900) {
                     $date = 1;
                 }
                 return (float) \PHPExcel\Shared\Date::FormattedPHPToExcel($calendar, 1, $date, $hour, $minute, $second);
diff --git a/src/PhpSpreadsheet/Calculation/TextData.php b/src/PhpSpreadsheet/Calculation/TextData.php
index f8102738..9e29391b 100644
--- a/src/PhpSpreadsheet/Calculation/TextData.php
+++ b/src/PhpSpreadsheet/Calculation/TextData.php
@@ -593,7 +593,7 @@ class TextData
         $value  = Functions::flattenSingleValue($value);
         $format = Functions::flattenSingleValue($format);
 
-        if ((is_string($value)) && (!is_numeric($value)) && PHPExcel\Shared\Date::isDateTimeFormatCode($format)) {
+        if ((is_string($value)) && (!is_numeric($value)) && \PHPExcel\Shared\Date::isDateTimeFormatCode($format)) {
             $value = DateTime::DATEVALUE($value);
         }
 
diff --git a/src/PhpSpreadsheet/IOFactory.php b/src/PhpSpreadsheet/IOFactory.php
index 2fbce12b..a5aaafbd 100644
--- a/src/PhpSpreadsheet/IOFactory.php
+++ b/src/PhpSpreadsheet/IOFactory.php
@@ -114,12 +114,12 @@ class IOFactory
      *
      * @static
      * @access    public
-     * @param    PHPExcel $phpExcel
+     * @param    Spreadsheet $phpExcel
      * @param    string  $writerType    Example: Excel2007
      * @return    Writer\IWriter
      * @throws    Writer\Exception
      */
-    public static function createWriter(PHPExcel $phpExcel, $writerType = '')
+    public static function createWriter(Spreadsheet $phpExcel, $writerType = '')
     {
         // Search type
         $searchType = 'IWriter';
@@ -171,12 +171,12 @@ class IOFactory
     }
 
     /**
-     * Loads PHPExcel from file using automatic Reader\IReader resolution
+     * Loads Spreadsheet from file using automatic Reader\IReader resolution
      *
      * @static
      * @access public
      * @param     string         $pFilename        The name of the spreadsheet file
-     * @return    PHPExcel
+     * @return    Spreadsheet
      * @throws    Reader\Exception
      */
     public static function load($pFilename)
diff --git a/src/PhpSpreadsheet/Reader/CSV.php b/src/PhpSpreadsheet/Reader/CSV.php
index 33a1e00c..937feee0 100644
--- a/src/PhpSpreadsheet/Reader/CSV.php
+++ b/src/PhpSpreadsheet/Reader/CSV.php
@@ -194,16 +194,16 @@ class CSV extends BaseReader implements IReader
     }
 
     /**
-     * Loads PHPExcel from file
+     * Loads Spreadsheet from file
      *
      * @param     string         $pFilename
-     * @return PHPExcel
+     * @return \PHPExcel\Spreadsheet
      * @throws Exception
      */
     public function load($pFilename)
     {
-        // Create new PHPExcel
-        $objPHPExcel = new PHPExcel();
+        // Create new Spreadsheet
+        $objPHPExcel = new \PHPExcel\Spreadsheet();
 
         // Load into this instance
         return $this->loadIntoExisting($pFilename, $objPHPExcel);
diff --git a/src/PhpSpreadsheet/Reader/Excel2003XML.php b/src/PhpSpreadsheet/Reader/Excel2003XML.php
index f57478e4..8ba1c0f6 100644
--- a/src/PhpSpreadsheet/Reader/Excel2003XML.php
+++ b/src/PhpSpreadsheet/Reader/Excel2003XML.php
@@ -218,7 +218,7 @@ class Excel2003XML extends BaseReader implements IReader
      * Loads PHPExcel from file
      *
      * @param     string         $pFilename
-     * @return     Spreadsheet
+     * @return     \PHPExcel\Spreadsheet
      * @throws     Exception
      */
     public function load($pFilename)
diff --git a/src/PhpSpreadsheet/Reader/Excel2007.php b/src/PhpSpreadsheet/Reader/Excel2007.php
index d690abb7..74376c8d 100644
--- a/src/PhpSpreadsheet/Reader/Excel2007.php
+++ b/src/PhpSpreadsheet/Reader/Excel2007.php
@@ -364,7 +364,7 @@ class Excel2007 extends BaseReader implements IReader
         }
 
         // Initialisations
-        $excel = new Spreadsheet;
+        $excel = new \PHPExcel\Spreadsheet;
         $excel->removeSheetByIndex(0);
         if (!$this->readDataOnly) {
             $excel->removeCellStyleXfByIndex(0); // remove the default style
diff --git a/src/PhpSpreadsheet/Reader/Excel5.php b/src/PhpSpreadsheet/Reader/Excel5.php
index 54f67eaa..7243a717 100644
--- a/src/PhpSpreadsheet/Reader/Excel5.php
+++ b/src/PhpSpreadsheet/Reader/Excel5.php
@@ -195,7 +195,7 @@ class Excel5 extends BaseReader implements IReader
     /**
      * Workbook to be returned by the reader.
      *
-     * @var Spreadsheet
+     * @var \PHPExcel\Spreadsheet
      */
     private $phpExcel;
 
diff --git a/src/PhpSpreadsheet/Reader/OOCalc.php b/src/PhpSpreadsheet/Reader/OOCalc.php
index 12080507..81a827d1 100644
--- a/src/PhpSpreadsheet/Reader/OOCalc.php
+++ b/src/PhpSpreadsheet/Reader/OOCalc.php
@@ -290,13 +290,13 @@ class OOCalc extends BaseReader implements IReader
      * Loads PHPExcel from file
      *
      * @param     string         $pFilename
-     * @return     Spreadsheet
+     * @return     \PHPExcel\Spreadsheet
      * @throws     Exception
      */
     public function load($pFilename)
     {
-        // Create new PHPExcel
-        $objPHPExcel = new PHPExcel();
+        // Create new Spreadsheet
+        $objPHPExcel = new \PHPExcel\Spreadsheet();
 
         // Load into this instance
         return $this->loadIntoExisting($pFilename, $objPHPExcel);
@@ -318,8 +318,8 @@ class OOCalc extends BaseReader implements IReader
      * Loads PHPExcel from file into PHPExcel instance
      *
      * @param     string         $pFilename
-     * @param    Spreadsheet    $objPHPExcel
-     * @return     Spreadsheet
+     * @param    \PHPExcel\Spreadsheet    $objPHPExcel
+     * @return     \PHPExcel\Spreadsheet
      * @throws     Exception
      */
     public function loadIntoExisting($pFilename, PHPExcel $objPHPExcel)
@@ -330,7 +330,7 @@ class OOCalc extends BaseReader implements IReader
         }
 
         $timezoneObj = new DateTimeZone('Europe/London');
-        $GMT = new DateTimeZone('UTC');
+        $GMT = new \DateTimeZone('UTC');
 
         $zipClass = \PHPExcel\Settings::getZipClass();
 
diff --git a/src/PhpSpreadsheet/Reader/SYLK.php b/src/PhpSpreadsheet/Reader/SYLK.php
index a28f2d53..126a3650 100644
--- a/src/PhpSpreadsheet/Reader/SYLK.php
+++ b/src/PhpSpreadsheet/Reader/SYLK.php
@@ -184,13 +184,13 @@ class SYLK extends BaseReader implements IReader
      * Loads PHPExcel from file
      *
      * @param     string         $pFilename
-     * @return     Spreadsheet
+     * @return     \PHPExcel\Spreadsheet
      * @throws     Exception
      */
     public function load($pFilename)
     {
-        // Create new PHPExcel
-        $objPHPExcel = new Spreadsheet();
+        // Create new Spreadsheet
+        $objPHPExcel = new \PHPExcel\Spreadsheet();
 
         // Load into this instance
         return $this->loadIntoExisting($pFilename, $objPHPExcel);
@@ -200,11 +200,11 @@ class SYLK extends BaseReader implements IReader
      * Loads PHPExcel from file into PHPExcel instance
      *
      * @param     string         $pFilename
-     * @param     Spreadsheet    $objPHPExcel
-     * @return    Spreadsheet
+     * @param     \PHPExcel\Spreadsheet    $objPHPExcel
+     * @return    \PHPExcel\Spreadsheet
      * @throws    Exception
      */
-    public function loadIntoExisting($pFilename, Spreadsheet $objPHPExcel)
+    public function loadIntoExisting($pFilename, \PHPExcel\Spreadsheet $objPHPExcel)
     {
         // Open file
         $this->openFile($pFilename);
diff --git a/src/PhpSpreadsheet/Writer/CSV.php b/src/PhpSpreadsheet/Writer/CSV.php
index e4dad06c..3bcee0ca 100644
--- a/src/PhpSpreadsheet/Writer/CSV.php
+++ b/src/PhpSpreadsheet/Writer/CSV.php
@@ -81,9 +81,9 @@ class CSV extends BaseWriter implements IWriter
     /**
      * Create a new CSV
      *
-     * @param    Spreadsheet    $phpExcel    Spreadsheet object
+     * @param    \PHPExcel\Spreadsheet    $phpExcel    Spreadsheet object
      */
-    public function __construct(Spreadsheet $phpExcel)
+    public function __construct(\PHPExcel\Spreadsheet $phpExcel)
     {
         $this->phpExcel = $phpExcel;
     }
diff --git a/src/PhpSpreadsheet/Writer/Excel2007.php b/src/PhpSpreadsheet/Writer/Excel2007.php
index 8f2eaa00..f1469e04 100644
--- a/src/PhpSpreadsheet/Writer/Excel2007.php
+++ b/src/PhpSpreadsheet/Writer/Excel2007.php
@@ -1,5 +1,7 @@
 <?php
 
+namespace PHPExcel\Writer;
+
 /**
  * PHPExcel_Writer_Excel2007
  *
@@ -25,7 +27,7 @@
  * @license    http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt    LGPL
  * @version    ##VERSION##, ##DATE##
  */
-class PHPExcel_Writer_Excel2007 extends PHPExcel_Writer_Abstract implements PHPExcel_Writer_IWriter
+class Excel2007 extends BaseWriter implements IWriter
 {
     /**
      * Pre-calculate formulas
@@ -48,14 +50,14 @@ class PHPExcel_Writer_Excel2007 extends PHPExcel_Writer_Abstract implements PHPE
     /**
      * Private writer parts
      *
-     * @var PHPExcel_Writer_Excel2007_WriterPart[]
+     * @var Excel2007\WriterPart[]
      */
     private $writerParts    = array();
 
     /**
-     * Private PHPExcel
+     * Private Spreadsheet
      *
-     * @var PHPExcel
+     * @var \PHPExcel\Spreadsheet
      */
     private $spreadSheet;
 
@@ -67,9 +69,9 @@ class PHPExcel_Writer_Excel2007 extends PHPExcel_Writer_Abstract implements PHPE
     private $stringTable    = array();
 
     /**
-     * Private unique PHPExcel_Style_Conditional HashTable
+     * Private unique \PHPExcel\Style\Conditional HashTable
      *
-     * @var PHPExcel_HashTable
+     * @var \PHPExcel\HashTable
      */
     private $stylesConditionalHashTable;
 
@@ -81,37 +83,37 @@ class PHPExcel_Writer_Excel2007 extends PHPExcel_Writer_Abstract implements PHPE
     private $styleHashTable;
 
     /**
-     * Private unique PHPExcel_Style_Fill HashTable
+     * Private unique \PHPExcel\Style\Fill HashTable
      *
-     * @var PHPExcel_HashTable
+     * @var \PHPExcel\HashTable
      */
     private $fillHashTable;
 
     /**
-     * Private unique PHPExcel_Style_Font HashTable
+     * Private unique \PHPExcel\Style\Font HashTable
      *
-     * @var PHPExcel_HashTable
+     * @var \PHPExcel\HashTable
      */
     private $fontHashTable;
 
     /**
-     * Private unique PHPExcel_Style_Borders HashTable
+     * Private unique \PHPExcel\Style\Borders HashTable
      *
-     * @var PHPExcel_HashTable
+     * @var \PHPExcel\HashTable
      */
     private $bordersHashTable ;
 
     /**
-     * Private unique PHPExcel_Style_NumberFormat HashTable
+     * Private unique \PHPExcel\Style\NumberFormat HashTable
      *
-     * @var PHPExcel_HashTable
+     * @var \PHPExcel\HashTable
      */
     private $numFmtHashTable;
 
     /**
-     * Private unique PHPExcel_Worksheet_BaseDrawing HashTable
+     * Private unique \PHPExcel\Worksheet\BaseDrawing HashTable
      *
-     * @var PHPExcel_HashTable
+     * @var \PHPExcel\HashTable
      */
     private $drawingHashTable;
 
@@ -120,25 +122,26 @@ class PHPExcel_Writer_Excel2007 extends PHPExcel_Writer_Abstract implements PHPE
      *
      * @param     PHPExcel    $pPHPExcel
      */
-    public function __construct(PHPExcel $pPHPExcel = null)
+    public function __construct(\PHPExcel\Spreadsheet $pPHPExcel = null)
     {
         // Assign PHPExcel
         $this->setPHPExcel($pPHPExcel);
 
-        $writerPartsArray = array(  'stringtable'       => 'PHPExcel_Writer_Excel2007_StringTable',
-                                    'contenttypes'      => 'PHPExcel_Writer_Excel2007_ContentTypes',
-                                    'docprops'          => 'PHPExcel_Writer_Excel2007_DocProps',
-                                    'rels'              => 'PHPExcel_Writer_Excel2007_Rels',
-                                    'theme'             => 'PHPExcel_Writer_Excel2007_Theme',
-                                    'style'             => 'PHPExcel_Writer_Excel2007_Style',
-                                    'workbook'          => 'PHPExcel_Writer_Excel2007_Workbook',
-                                    'worksheet'         => 'PHPExcel_Writer_Excel2007_Worksheet',
-                                    'drawing'           => 'PHPExcel_Writer_Excel2007_Drawing',
-                                    'comments'          => 'PHPExcel_Writer_Excel2007_Comments',
-                                    'chart'             => 'PHPExcel_Writer_Excel2007_Chart',
-                                    'relsvba'           => 'PHPExcel_Writer_Excel2007_RelsVBA',
-                                    'relsribbonobjects' => 'PHPExcel_Writer_Excel2007_RelsRibbon'
-                                 );
+        $writerPartsArray = [
+            'stringtable'       => '\\PHPExcel\\Writer\\Excel2007\\StringTable',
+            'contenttypes'      => '\\PHPExcel\\Writer\\Excel2007\\ContentTypes',
+            'docprops'          => '\\PHPExcel\\Writer\\Excel2007\\DocProps',
+            'rels'              => '\\PHPExcel\\Writer\\Excel2007\\Rels',
+            'theme'             => '\\PHPExcel\\Writer\\Excel2007\\Theme',
+            'style'             => '\\PHPExcel\\Writer\\Excel2007\\Style',
+            'workbook'          => '\\PHPExcel\\Writer\\Excel2007\\Workbook',
+            'worksheet'         => '\\PHPExcel\\Writer\\Excel2007\\Worksheet',
+            'drawing'           => '\\PHPExcel\\Writer\\Excel2007\\Drawing',
+            'comments'          => '\\PHPExcel\\Writer\\Excel2007\\Comments',
+            'chart'             => '\\PHPExcel\\Writer\\Excel2007\\Chart',
+            'relsvba'           => '\\PHPExcel\\Writer\\Excel2007\\RelsVBA',
+            'relsribbonobjects' => '\\PHPExcel\\Writer\\Excel2007\\RelsRibbon'
+        ];
 
         //    Initialise writer parts
         //        and Assign their parent IWriters
@@ -419,11 +422,11 @@ class PHPExcel_Writer_Excel2007 extends PHPExcel_Writer_Abstract implements PHPE
     /**
      * Set PHPExcel object
      *
-     * @param     PHPExcel     $pPHPExcel    PHPExcel object
-     * @throws    PHPExcel_Writer_Exception
-     * @return PHPExcel_Writer_Excel2007
+     * @param     \PHPExcel\Spreadsheet     $pPHPExcel    PHPExcel object
+     * @throws    Exception
+     * @return    Excel2007
      */
-    public function setPHPExcel(PHPExcel $pPHPExcel = null)
+    public function setPHPExcel(\PHPExcel\Spreadsheet $pPHPExcel = null)
     {
         $this->spreadSheet = $pPHPExcel;
         return $this;
diff --git a/src/PhpSpreadsheet/Writer/Excel2007/StringTable.php b/src/PhpSpreadsheet/Writer/Excel2007/StringTable.php
index fccec669..d1ce0ae5 100644
--- a/src/PhpSpreadsheet/Writer/Excel2007/StringTable.php
+++ b/src/PhpSpreadsheet/Writer/Excel2007/StringTable.php
@@ -1,5 +1,7 @@
 <?php
 
+namespace PHPExcel\Writer\Excel2007;
+
 /**
  * PHPExcel_Writer_Excel2007_StringTable
  *
@@ -25,12 +27,12 @@
  * @license    http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt    LGPL
  * @version    ##VERSION##, ##DATE##
  */
-class PHPExcel_Writer_Excel2007_StringTable extends PHPExcel_Writer_Excel2007_WriterPart
+class StringTable extends WriterPart
 {
     /**
      * Create worksheet stringtable
      *
-     * @param     PHPExcel_Worksheet     $pSheet                Worksheet
+     * @param     \PHPExcel\Worksheet     $pSheet                Worksheet
      * @param     string[]                 $pExistingTable     Existing table to eventually merge with
      * @return     string[]                 String table for worksheet
      * @throws     PHPExcel_Writer_Exception
diff --git a/src/PhpSpreadsheet/Writer/Excel2007/WriterPart.php b/src/PhpSpreadsheet/Writer/Excel2007/WriterPart.php
index 806ebe51..ca04f650 100644
--- a/src/PhpSpreadsheet/Writer/Excel2007/WriterPart.php
+++ b/src/PhpSpreadsheet/Writer/Excel2007/WriterPart.php
@@ -1,5 +1,7 @@
 <?php
 
+namespace PHPExcel\Writer\Excel2007;
+
 /**
  * PHPExcel_Writer_Excel2007_WriterPart
  *
@@ -25,22 +27,22 @@
  * @license    http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt    LGPL
  * @version    ##VERSION##, ##DATE##
  */
-abstract class PHPExcel_Writer_Excel2007_WriterPart
+abstract class WriterPart
 {
     /**
      * Parent IWriter object
      *
-     * @var PHPExcel_Writer_IWriter
+     * @var \PHPExcel\Writer\IWriter
      */
     private $parentWriter;
 
     /**
      * Set parent IWriter object
      *
-     * @param PHPExcel_Writer_IWriter    $pWriter
-     * @throws PHPExcel_Writer_Exception
+     * @param \PHPExcel\Writer\IWriter    $pWriter
+     * @throws \PHPExcel\Writer\Exception
      */
-    public function setParentWriter(PHPExcel_Writer_IWriter $pWriter = null)
+    public function setParentWriter(\PHPExcel\Writer\IWriter $pWriter = null)
     {
         $this->parentWriter = $pWriter;
     }
@@ -48,25 +50,25 @@ abstract class PHPExcel_Writer_Excel2007_WriterPart
     /**
      * Get parent IWriter object
      *
-     * @return PHPExcel_Writer_IWriter
-     * @throws PHPExcel_Writer_Exception
+     * @return \PHPExcel\Writer\IWriter
+     * @throws \PHPExcel\Writer\Exception
      */
     public function getParentWriter()
     {
         if (!is_null($this->parentWriter)) {
             return $this->parentWriter;
         } else {
-            throw new PHPExcel_Writer_Exception("No parent PHPExcel_Writer_IWriter assigned.");
+            throw new \PHPExcel\Writer\Exception("No parent \PHPExcel\Writer\IWriter assigned.");
         }
     }
 
     /**
      * Set parent IWriter object
      *
-     * @param PHPExcel_Writer_IWriter    $pWriter
-     * @throws PHPExcel_Writer_Exception
+     * @param \PHPExcel\Writer\IWriter    $pWriter
+     * @throws \PHPExcel\Writer\Exception
      */
-    public function __construct(PHPExcel_Writer_IWriter $pWriter = null)
+    public function __construct(\PHPExcel\Writer\IWriter $pWriter = null)
     {
         if (!is_null($pWriter)) {
             $this->parentWriter = $pWriter;
diff --git a/src/PhpSpreadsheet/Writer/PDF/Core.php b/src/PhpSpreadsheet/Writer/PDF/Core.php
index 71a614f1..5a96bcf1 100644
--- a/src/PhpSpreadsheet/Writer/PDF/Core.php
+++ b/src/PhpSpreadsheet/Writer/PDF/Core.php
@@ -208,9 +208,9 @@ abstract class Core extends \PHPExcel\Writer\HTML
     /**
      *  Create a new PDF Writer instance
      *
-     *  @param     Spreadsheet    $phpExcel    Spreadsheet object
+     *  @param     \PHPExcel\Spreadsheet    $phpExcel    Spreadsheet object
      */
-    public function __construct(Spreadsheet $phpExcel)
+    public function __construct(\PHPExcel\Spreadsheet $phpExcel)
     {
         parent::__construct($phpExcel);
         $this->setUseInlineCss(true);
diff --git a/src/PhpSpreadsheet/Writer/PDF/DomPDF.php b/src/PhpSpreadsheet/Writer/PDF/DomPDF.php
index 1e02cb0e..fffde763 100644
--- a/src/PhpSpreadsheet/Writer/PDF/DomPDF.php
+++ b/src/PhpSpreadsheet/Writer/PDF/DomPDF.php
@@ -40,9 +40,9 @@ class DomPDF extends Core implements \PHPExcel\Writer\IWriter
     /**
      *  Create a new DomPDF Writer instance
      *
-     *  @param   Spreadsheet    $phpExcel    Spreadsheet object
+     *  @param   \PHPExcel\Spreadsheet    $phpExcel    Spreadsheet object
      */
-    public function __construct(Spreadsheet $phpExcel)
+    public function __construct(\PHPExcel\Spreadsheet $phpExcel)
     {
         parent::__construct($phpExcel);
     }
@@ -51,7 +51,7 @@ class DomPDF extends Core implements \PHPExcel\Writer\IWriter
      *  Save Spreadsheet to file
      *
      *  @param   string     $pFilename   Name of the file to save as
-     *  @throws  PHPExcel_Writer_Exception
+     *  @throws  \PHPExcel\Writer\Exception
      */
     public function save($pFilename = null)
     {
diff --git a/src/PhpSpreadsheet/Writer/PDF/mPDF.php b/src/PhpSpreadsheet/Writer/PDF/mPDF.php
index 0627fdd0..7ae5570b 100644
--- a/src/PhpSpreadsheet/Writer/PDF/mPDF.php
+++ b/src/PhpSpreadsheet/Writer/PDF/mPDF.php
@@ -40,9 +40,9 @@ class mPDF extends Core implements \PHPExcel\Writer\IWriter
     /**
      *  Create a mPDF Writer instance
      *
-     *  @param  Spreadsheet  $phpExcel  Spreadsheet object
+     *  @param  \PHPExcel\Spreadsheet  $phpExcel  Spreadsheet object
      */
-    public function __construct(Spreadsheet $phpExcel)
+    public function __construct(\PHPExcel\Spreadsheet $phpExcel)
     {
         parent::__construct($phpExcel);
     }
diff --git a/src/PhpSpreadsheet/Writer/PDF/tcPDF.php b/src/PhpSpreadsheet/Writer/PDF/tcPDF.php
index f5fc92a3..854cf1d7 100644
--- a/src/PhpSpreadsheet/Writer/PDF/tcPDF.php
+++ b/src/PhpSpreadsheet/Writer/PDF/tcPDF.php
@@ -41,9 +41,9 @@ class tcPDF extends Core implements \PHPExcel\Writer\IWriter
     /**
      *  Create a new tcPDF Writer instance
      *
-     *  @param  Spreadsheet  $phpExcel  Spreadsheet object
+     *  @param  \PHPExcel\Spreadsheet  $phpExcel  Spreadsheet object
      */
-    public function __construct(Spreadsheet $phpExcel)
+    public function __construct(\PHPExcel\Spreadsheet $phpExcel)
     {
         parent::__construct($phpExcel);
     }