diff --git a/src/PhpWord/Writer/HTML/Element/Footnote.php b/src/PhpWord/Writer/HTML/Element/Footnote.php
index 888ba411..f1570ed0 100644
--- a/src/PhpWord/Writer/HTML/Element/Footnote.php
+++ b/src/PhpWord/Writer/HTML/Element/Footnote.php
@@ -38,6 +38,10 @@ class Footnote extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\Footnote) {
+            return;
+        }
+
         $noteId = count($this->parentWriter->getNotes()) + 1;
         $noteMark = $this->noteType . '-' . $this->element->getRelationId();
         $this->parentWriter->addNote($noteId, $noteMark);
diff --git a/src/PhpWord/Writer/HTML/Element/Image.php b/src/PhpWord/Writer/HTML/Element/Image.php
index 6ba272d9..3813146d 100644
--- a/src/PhpWord/Writer/HTML/Element/Image.php
+++ b/src/PhpWord/Writer/HTML/Element/Image.php
@@ -34,10 +34,11 @@ class Image extends Element
      */
     public function write()
     {
-        $html = '';
-        if (!$this->element instanceof ImageElement) {
-            return $html;
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\Text) {
+            return;
         }
+
+        $html = '';
         if (!$this->parentWriter->isPdf()) {
             $imageData = $this->getBase64ImageData($this->element);
             if (!is_null($imageData)) {
diff --git a/src/PhpWord/Writer/HTML/Element/Link.php b/src/PhpWord/Writer/HTML/Element/Link.php
index 5906205f..2792eb67 100644
--- a/src/PhpWord/Writer/HTML/Element/Link.php
+++ b/src/PhpWord/Writer/HTML/Element/Link.php
@@ -31,6 +31,10 @@ class Link extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\Link) {
+            return;
+        }
+
         $html = "<a href=\"{$this->element->getTarget()}\">{$this->element->getText()}</a>" . PHP_EOL;
         if (!$this->withoutP) {
             $html = '<p>' . $html . '</p>' . PHP_EOL;
diff --git a/src/PhpWord/Writer/HTML/Element/ListItem.php b/src/PhpWord/Writer/HTML/Element/ListItem.php
index 42675bbf..89f2ad69 100644
--- a/src/PhpWord/Writer/HTML/Element/ListItem.php
+++ b/src/PhpWord/Writer/HTML/Element/ListItem.php
@@ -31,6 +31,10 @@ class ListItem extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\ListItem) {
+            return;
+        }
+
         $text = htmlspecialchars($this->element->getTextObject()->getText());
         $html = '<p>' . $text . '</p>' . PHP_EOL;
 
diff --git a/src/PhpWord/Writer/HTML/Element/Table.php b/src/PhpWord/Writer/HTML/Element/Table.php
index 2c96a97a..b3974554 100644
--- a/src/PhpWord/Writer/HTML/Element/Table.php
+++ b/src/PhpWord/Writer/HTML/Element/Table.php
@@ -31,6 +31,10 @@ class Table extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\Table) {
+            return;
+        }
+
         $html = '';
         $rows = $this->element->getRows();
         $rowCount = count($rows);
diff --git a/src/PhpWord/Writer/HTML/Element/Text.php b/src/PhpWord/Writer/HTML/Element/Text.php
index 20b6ce79..dceb7a4d 100644
--- a/src/PhpWord/Writer/HTML/Element/Text.php
+++ b/src/PhpWord/Writer/HTML/Element/Text.php
@@ -36,6 +36,10 @@ class Text extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\Text) {
+            return;
+        }
+
         $html = '';
         // Paragraph style
         $paragraphStyle = $this->element->getParagraphStyle();
@@ -44,6 +48,8 @@ class Text extends Element
             $styleWriter = new ParagraphStyleWriter($paragraphStyle);
             $paragraphStyle = $styleWriter->write();
         }
+        $hasParagraphStyle = $paragraphStyle && !$this->withoutP;
+
         // Font style
         $fontStyle = $this->element->getFontStyle();
         $fontStyleIsObject = ($fontStyle instanceof Font);
@@ -52,7 +58,7 @@ class Text extends Element
             $fontStyle = $styleWriter->write();
         }
 
-        if ($paragraphStyle && !$this->withoutP) {
+        if ($hasParagraphStyle) {
             $attribute = $pStyleIsObject ? 'style' : 'class';
             $html .= "<p {$attribute}=\"{$paragraphStyle}\">";
         }
@@ -64,7 +70,7 @@ class Text extends Element
         if ($fontStyle) {
             $html .= '</span>';
         }
-        if ($paragraphStyle && !$this->withoutP) {
+        if ($hasParagraphStyle) {
             $html .= '</p>' . PHP_EOL;
         }
 
diff --git a/src/PhpWord/Writer/HTML/Element/TextRun.php b/src/PhpWord/Writer/HTML/Element/TextRun.php
index 02b24488..b6848d8f 100644
--- a/src/PhpWord/Writer/HTML/Element/TextRun.php
+++ b/src/PhpWord/Writer/HTML/Element/TextRun.php
@@ -34,6 +34,10 @@ class TextRun extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\TextRun) {
+            return;
+        }
+
         $html = '';
         $elements = $this->element->getElements();
         if (count($elements) > 0) {
diff --git a/src/PhpWord/Writer/HTML/Element/Title.php b/src/PhpWord/Writer/HTML/Element/Title.php
index 68633f1f..e2252241 100644
--- a/src/PhpWord/Writer/HTML/Element/Title.php
+++ b/src/PhpWord/Writer/HTML/Element/Title.php
@@ -31,6 +31,10 @@ class Title extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\Title) {
+            return;
+        }
+
         $tag = 'h' . $this->element->getDepth();
         $text = htmlspecialchars($this->element->getText());
         $html = "<{$tag}>{$text}</{$tag}>" . PHP_EOL;
diff --git a/src/PhpWord/Writer/ODText/Element/Image.php b/src/PhpWord/Writer/ODText/Element/Image.php
index 14408d66..ffe2d094 100644
--- a/src/PhpWord/Writer/ODText/Element/Image.php
+++ b/src/PhpWord/Writer/ODText/Element/Image.php
@@ -31,6 +31,10 @@ class Image extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\Image) {
+            return;
+        }
+
         $mediaIndex = $this->element->getMediaIndex();
         $target = 'Pictures/' . $this->element->getTarget();
         $style = $this->element->getStyle();
diff --git a/src/PhpWord/Writer/ODText/Element/Link.php b/src/PhpWord/Writer/ODText/Element/Link.php
index 9914b1cd..4ff094d2 100644
--- a/src/PhpWord/Writer/ODText/Element/Link.php
+++ b/src/PhpWord/Writer/ODText/Element/Link.php
@@ -29,6 +29,10 @@ class Link extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\Link) {
+            return;
+        }
+
         if (!$this->withoutP) {
             $this->xmlWriter->startElement('text:p'); // text:p
         }
diff --git a/src/PhpWord/Writer/ODText/Element/Table.php b/src/PhpWord/Writer/ODText/Element/Table.php
index fcd1461a..dbe5b14c 100644
--- a/src/PhpWord/Writer/ODText/Element/Table.php
+++ b/src/PhpWord/Writer/ODText/Element/Table.php
@@ -32,6 +32,10 @@ class Table extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\Table) {
+            return;
+        }
+
         $rows = $this->element->getRows();
         $rowCount = count($rows);
         $colCount = $this->element->countColumns();
diff --git a/src/PhpWord/Writer/ODText/Element/Text.php b/src/PhpWord/Writer/ODText/Element/Text.php
index 0c94bf0b..ee2fafab 100644
--- a/src/PhpWord/Writer/ODText/Element/Text.php
+++ b/src/PhpWord/Writer/ODText/Element/Text.php
@@ -29,6 +29,10 @@ class Text extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\Text) {
+            return;
+        }
+
         $fontStyle = $this->element->getFontStyle();
         $paragraphStyle = $this->element->getParagraphStyle();
 
diff --git a/src/PhpWord/Writer/ODText/Element/TextRun.php b/src/PhpWord/Writer/ODText/Element/TextRun.php
index 3627f148..b03fc353 100644
--- a/src/PhpWord/Writer/ODText/Element/TextRun.php
+++ b/src/PhpWord/Writer/ODText/Element/TextRun.php
@@ -17,6 +17,7 @@
 
 namespace PhpOffice\PhpWord\Writer\ODText\Element;
 
+use PhpOffice\PhpWord\Element\Link as LinkElement;
 use PhpOffice\PhpWord\Element\Text as TextElement;
 
 /**
@@ -31,6 +32,10 @@ class TextRun extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\TextRun) {
+            return;
+        }
+
         $elements = $this->element->getElements();
         $this->xmlWriter->startElement('text:p');
         if (count($elements) > 0) {
@@ -38,7 +43,7 @@ class TextRun extends Element
                 if ($element instanceof TextElement) {
                     $elementWriter = new Text($this->xmlWriter, $this->parentWriter, $element, true);
                     $elementWriter->write();
-                } elseif ($element instanceof Link) {
+                } elseif ($element instanceof LinkElement) {
                     $elementWriter = new Link($this->xmlWriter, $this->parentWriter, $element, true);
                     $elementWriter->write();
                 }
diff --git a/src/PhpWord/Writer/RTF/Element/Text.php b/src/PhpWord/Writer/RTF/Element/Text.php
index 83ade9d2..8b71b390 100644
--- a/src/PhpWord/Writer/RTF/Element/Text.php
+++ b/src/PhpWord/Writer/RTF/Element/Text.php
@@ -33,6 +33,10 @@ class Text extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\Text) {
+            return;
+        }
+
         $rtfText = '';
 
         $fontStyle = $this->element->getFontStyle();
diff --git a/src/PhpWord/Writer/RTF/Element/TextRun.php b/src/PhpWord/Writer/RTF/Element/TextRun.php
index 775282e0..f5df5d96 100644
--- a/src/PhpWord/Writer/RTF/Element/TextRun.php
+++ b/src/PhpWord/Writer/RTF/Element/TextRun.php
@@ -33,7 +33,12 @@ class TextRun extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\TextRun) {
+            return;
+        }
+
         $rtfText = '';
+
         $elements = $this->element->getElements();
         if (count($elements) > 0) {
             $rtfText .= '\pard\nowidctlpar' . PHP_EOL;
diff --git a/src/PhpWord/Writer/RTF/Element/Title.php b/src/PhpWord/Writer/RTF/Element/Title.php
index 524c005d..5915c42e 100644
--- a/src/PhpWord/Writer/RTF/Element/Title.php
+++ b/src/PhpWord/Writer/RTF/Element/Title.php
@@ -31,7 +31,12 @@ class Title extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\Title) {
+            return;
+        }
+
         $rtfText = '';
+
         $rtfText .= '\pard\nowidctlpar' . PHP_EOL;
         $rtfText .= $this->element->getText();
         $rtfText .= '\par' . PHP_EOL;
diff --git a/src/PhpWord/Writer/Word2007/Element/CheckBox.php b/src/PhpWord/Writer/Word2007/Element/CheckBox.php
index 543a49b4..ef8c166d 100644
--- a/src/PhpWord/Writer/Word2007/Element/CheckBox.php
+++ b/src/PhpWord/Writer/Word2007/Element/CheckBox.php
@@ -33,6 +33,10 @@ class CheckBox extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\CheckBox) {
+            return;
+        }
+
         $name = htmlspecialchars($this->element->getName());
         $name = String::controlCharacterPHP2OOXML($name);
         $text = htmlspecialchars($this->element->getText());
diff --git a/src/PhpWord/Writer/Word2007/Element/Footnote.php b/src/PhpWord/Writer/Word2007/Element/Footnote.php
index b5d88727..f1f276aa 100644
--- a/src/PhpWord/Writer/Word2007/Element/Footnote.php
+++ b/src/PhpWord/Writer/Word2007/Element/Footnote.php
@@ -36,6 +36,10 @@ class Footnote extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\Footnote) {
+            return;
+        }
+
         if (!$this->withoutP) {
             $this->xmlWriter->startElement('w:p');
         }
diff --git a/src/PhpWord/Writer/Word2007/Element/Image.php b/src/PhpWord/Writer/Word2007/Element/Image.php
index 214b8a2a..6b948f1e 100644
--- a/src/PhpWord/Writer/Word2007/Element/Image.php
+++ b/src/PhpWord/Writer/Word2007/Element/Image.php
@@ -43,6 +43,10 @@ class Image extends Element
      */
     private function writeImage()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\Image) {
+            return;
+        }
+
         $rId = $this->element->getRelationId() + ($this->element->isInSection() ? 6 : 0);
         $style = $this->element->getStyle();
         $styleWriter = new ImageStyleWriter($this->xmlWriter, $style);
diff --git a/src/PhpWord/Writer/Word2007/Element/Link.php b/src/PhpWord/Writer/Word2007/Element/Link.php
index 2342b312..2e53b1a8 100644
--- a/src/PhpWord/Writer/Word2007/Element/Link.php
+++ b/src/PhpWord/Writer/Word2007/Element/Link.php
@@ -32,6 +32,10 @@ class Link extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\Link) {
+            return;
+        }
+
         $rId = $this->element->getRelationId() + ($this->element->isInSection() ? 6 : 0);
         $fontStyle = $this->element->getFontStyle();
         $paragraphStyle = $this->element->getParagraphStyle();
diff --git a/src/PhpWord/Writer/Word2007/Element/ListItem.php b/src/PhpWord/Writer/Word2007/Element/ListItem.php
index df8621ff..e4394862 100644
--- a/src/PhpWord/Writer/Word2007/Element/ListItem.php
+++ b/src/PhpWord/Writer/Word2007/Element/ListItem.php
@@ -32,6 +32,10 @@ class ListItem extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\ListItem) {
+            return;
+        }
+
         $textObject = $this->element->getTextObject();
         $depth = $this->element->getDepth();
         $numId = $this->element->getStyle()->getNumId();
diff --git a/src/PhpWord/Writer/Word2007/Element/Object.php b/src/PhpWord/Writer/Word2007/Element/Object.php
index 6e6a1cbb..db90d78c 100644
--- a/src/PhpWord/Writer/Word2007/Element/Object.php
+++ b/src/PhpWord/Writer/Word2007/Element/Object.php
@@ -29,6 +29,10 @@ class Object extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\Object) {
+            return;
+        }
+
         $rIdObject = $this->element->getRelationId() + ($this->element->isInSection() ? 6 : 0);
         $rIdImage = $this->element->getImageRelationId() + ($this->element->isInSection() ? 6 : 0);
         $shapeId = md5($rIdObject . '_' . $rIdImage);
diff --git a/src/PhpWord/Writer/Word2007/Element/PreserveText.php b/src/PhpWord/Writer/Word2007/Element/PreserveText.php
index f09af49c..63c03899 100644
--- a/src/PhpWord/Writer/Word2007/Element/PreserveText.php
+++ b/src/PhpWord/Writer/Word2007/Element/PreserveText.php
@@ -33,6 +33,10 @@ class PreserveText extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\PreserveText) {
+            return;
+        }
+
         $fontStyle = $this->element->getFontStyle();
         $paragraphStyle = $this->element->getParagraphStyle();
         $texts = $this->element->getText();
diff --git a/src/PhpWord/Writer/Word2007/Element/TOC.php b/src/PhpWord/Writer/Word2007/Element/TOC.php
index 1ebde1a9..e4542bcb 100644
--- a/src/PhpWord/Writer/Word2007/Element/TOC.php
+++ b/src/PhpWord/Writer/Word2007/Element/TOC.php
@@ -34,6 +34,10 @@ class TOC extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\TOC) {
+            return;
+        }
+
         $titles = $this->element->getTitles();
         $writeFieldMark = true;
 
@@ -55,6 +59,9 @@ class TOC extends Element
 
     /**
      * Write title
+     *
+     * @param \PhpOffice\PhpWord\Element\Title $title
+     * @param bool $writeFieldMark
      */
     private function writeTitle($title, $writeFieldMark)
     {
diff --git a/src/PhpWord/Writer/Word2007/Element/Table.php b/src/PhpWord/Writer/Word2007/Element/Table.php
index 07863979..3a29f410 100644
--- a/src/PhpWord/Writer/Word2007/Element/Table.php
+++ b/src/PhpWord/Writer/Word2007/Element/Table.php
@@ -36,6 +36,10 @@ class Table extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\Table) {
+            return;
+        }
+
         $rows = $this->element->getRows();
         $rowCount = count($rows);
 
diff --git a/src/PhpWord/Writer/Word2007/Element/Text.php b/src/PhpWord/Writer/Word2007/Element/Text.php
index a6621a05..c271174f 100644
--- a/src/PhpWord/Writer/Word2007/Element/Text.php
+++ b/src/PhpWord/Writer/Word2007/Element/Text.php
@@ -33,6 +33,10 @@ class Text extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\Text) {
+            return;
+        }
+
         $fontStyle = $this->element->getFontStyle();
         $paragraphStyle = $this->element->getParagraphStyle();
         $text = htmlspecialchars($this->element->getText());
diff --git a/src/PhpWord/Writer/Word2007/Element/TextRun.php b/src/PhpWord/Writer/Word2007/Element/TextRun.php
index 6d761b4f..d4b2d291 100644
--- a/src/PhpWord/Writer/Word2007/Element/TextRun.php
+++ b/src/PhpWord/Writer/Word2007/Element/TextRun.php
@@ -31,6 +31,10 @@ class TextRun extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\TextRun) {
+            return;
+        }
+
         $paragraphStyle = $this->element->getParagraphStyle();
         $styleWriter = new ParagraphStyleWriter($this->xmlWriter, $paragraphStyle);
         $styleWriter->setIsInline(true);
diff --git a/src/PhpWord/Writer/Word2007/Element/Title.php b/src/PhpWord/Writer/Word2007/Element/Title.php
index c55a60a7..e1c7a0ae 100644
--- a/src/PhpWord/Writer/Word2007/Element/Title.php
+++ b/src/PhpWord/Writer/Word2007/Element/Title.php
@@ -31,6 +31,10 @@ class Title extends Element
      */
     public function write()
     {
+        if (!$this->element instanceof \PhpOffice\PhpWord\Element\Title) {
+            return;
+        }
+
         $bookmarkId = $this->element->getBookmarkId();
         $anchor = '_Toc' . ($bookmarkId + 252634154);
         $style = $this->element->getStyle();
diff --git a/src/PhpWord/Writer/Word2007/Part/Rels.php b/src/PhpWord/Writer/Word2007/Part/Rels.php
index 22480ce2..95ac32b1 100644
--- a/src/PhpWord/Writer/Word2007/Part/Rels.php
+++ b/src/PhpWord/Writer/Word2007/Part/Rels.php
@@ -72,7 +72,7 @@ class Rels extends AbstractPart
         }
 
         // Media relationships
-        if (!is_null($mediaRels) && is_array($mediaRels)) {
+        if (is_array($mediaRels)) {
             $mapping = array('image' => 'image', 'object' => 'oleObject', 'link' => 'hyperlink');
             $targetPaths = array('image' => 'media/', 'object' => 'embeddings/');
             foreach ($mediaRels as $mediaRel) {