diff --git a/Spreadsheet/Excel/Writer/Workbook.php b/Spreadsheet/Excel/Writer/Workbook.php
index 6d1cb9c..ed9998b 100644
--- a/Spreadsheet/Excel/Writer/Workbook.php
+++ b/Spreadsheet/Excel/Writer/Workbook.php
@@ -178,6 +178,9 @@ class Spreadsheet_Excel_Writer_Workbook extends Spreadsheet_Excel_Writer_BIFFwri
     /** @var array */
     public $blockSize;
 
+    /** @var int */
+    public $timestamp;
+
     /**
     * Class constructor
     *
@@ -213,6 +216,8 @@ class Spreadsheet_Excel_Writer_Workbook extends Spreadsheet_Excel_Writer_BIFFwri
         $this->totalStringLength    = 0;
         $this->uniqueString         = 0;
         $this->tableOfStrings       = array();
+        $this->timestamp            = time();
+
         $this->setPaletteXl97();
     }
 
@@ -636,7 +641,7 @@ class Spreadsheet_Excel_Writer_Workbook extends Spreadsheet_Excel_Writer_BIFFwri
             }
         }
 
-        $root = new OLE_PPS_Root(time(), time(), array($OLE));
+        $root = new OLE_PPS_Root($this->timestamp, $this->timestamp, array($OLE));
 
         if ($this->temporaryDirectory != '') {
             $root->setTempDir($this->temporaryDirectory);
diff --git a/test/Test/Spreadsheet/Excel/Writer/Test_Spreadsheet_Excel_WriterTestCase.php b/test/Test/Spreadsheet/Excel/Writer/Test_Spreadsheet_Excel_WriterTestCase.php
index 69d6623..00faa30 100644
--- a/test/Test/Spreadsheet/Excel/Writer/Test_Spreadsheet_Excel_WriterTestCase.php
+++ b/test/Test/Spreadsheet/Excel/Writer/Test_Spreadsheet_Excel_WriterTestCase.php
@@ -6,12 +6,50 @@
  */
 class Test_Spreadsheet_Excel_WriterTestCase extends PHPUnit_Framework_TestCase
 {
+    const FIXTURES_PATH = 'test/fixture/';
+
     /**
-     * @param string $fileName
-     * @return Spreadsheet_Excel_Writer_Workbook
+     * @param string $filename
+     * @return Spreadsheet_Excel_Writer
      */
-    protected function getNewWorkbook($fileName = 'my_workbook')
+    protected function getNewWorkbook($filename = '')
     {
-        return new Spreadsheet_Excel_Writer_Workbook($fileName);
+        // we're writing to the standard output by defaulr
+        return new Spreadsheet_Excel_Writer($filename);
+    }
+
+    protected function assertSameAsInFixture($filename, Spreadsheet_Excel_Writer $workbook)
+    {
+        $this->assertEmpty($workbook->fileName, "Testing with fixtures works only for standard output");
+
+        // we have to fix timestamp for fixtures to work
+        $workbook->timestamp = 1000000000; // somewhere in 2001
+
+        ob_start();
+        $workbook->close();
+        $data = ob_get_clean();
+
+        $fullPath = self::FIXTURES_PATH.$filename;
+
+        if ($this->shouldUpdateFixtures()) {
+            file_put_contents($fullPath, $data);
+        }
+
+        if (!is_file($fullPath)) {
+            $this->fail("Fixture $filename not found");
+        }
+
+        // TODO: should we save data for future analysis?
+        //file_put_contents("{$fullPath}.work", $data);
+
+        $this->assertEquals(file_get_contents($fullPath), $data, "Output differs for $filename");
+    }
+
+    /**
+     * We should update golden files
+     */
+    private function shouldUpdateFixtures()
+    {
+        return isset($_SERVER['GOLDEN']);
     }
 }
\ No newline at end of file
diff --git a/test/Test/Spreadsheet/Excel/Writer/Test_Spreadsheet_Excel_Writer_WorkbookTest.php b/test/Test/Spreadsheet/Excel/Writer/Test_Spreadsheet_Excel_Writer_WorkbookTest.php
index e96a5df..beb9a0e 100644
--- a/test/Test/Spreadsheet/Excel/Writer/Test_Spreadsheet_Excel_Writer_WorkbookTest.php
+++ b/test/Test/Spreadsheet/Excel/Writer/Test_Spreadsheet_Excel_Writer_WorkbookTest.php
@@ -10,6 +10,28 @@ class Test_Spreadsheet_Excel_Writer_WorkbookTest extends Test_Spreadsheet_Excel_
     {
         $workbook = $this->getNewWorkbook();
 
+        $before = get_object_vars($workbook);
+
+        $workbook->setVersion(1);
+
+        $this->assertEquals($before, get_object_vars($workbook), "Version 1 should not change internal state");
+
         $workbook->setVersion(8);
+
+        $this->assertNotEquals($before, get_object_vars($workbook), "Version 8 should change internal state");
+
+        return $workbook;
     }
-}
\ No newline at end of file
+
+    /**
+     * @depends testSetVersion
+     */
+    public function testWriteSingleCell(Spreadsheet_Excel_Writer $workbook)
+    {
+        $sheet = $workbook->addWorksheet("Example");
+        $sheet->write(0, 0, "Example");
+
+        $this->assertSameAsInFixture('example.xls', $workbook);
+    }
+
+}
diff --git a/test/fixture/example.xls b/test/fixture/example.xls
new file mode 100644
index 0000000..f7955b3
Binary files /dev/null and b/test/fixture/example.xls differ