diff --git a/core/document.cpp b/core/document.cpp
index 00a7ace5e..e817cca28 100644
--- a/core/document.cpp
+++ b/core/document.cpp
@@ -26,11 +26,11 @@
 
 // local includes
 #include "document.h"
+#include "observer.h"
 #include "page.h"
 #include "link.h"
-#include "conf/settings.h"
 #include "generator_pdf/generator_pdf.h"  // PDF generator
-//#include "generator_ps/generator_ps.H" // PS generator
+#include "conf/settings.h"
 
 // structures used internally by KPDFDocument for local variables storage
 class KPDFDocumentPrivate
diff --git a/core/document.h b/core/document.h
index 8f0ff6d0a..7b13ceba2 100644
--- a/core/document.h
+++ b/core/document.h
@@ -15,43 +15,14 @@
 #include <qstring.h>
 #include <qdom.h>
 
-class KPrinter;
 class KPDFPage;
 class KPDFLink;
-class Generator;
+class KPDFDocumentObserver;
 class DocumentInfo;
 class DocumentSynopsis;
+class Generator;
 class PixmapRequest;
-
-/**
- * @short Base class for objects being notified when something changes.
- *
- * Inherit this class and call KPDFDocument->addObserver( yourClass ) to get
- * notified of asyncronous events (new pixmap generated, or changed, etc..).
- */
-class KPDFDocumentObserver
-{
-    public:
-        // you must give each observer a unique ID (used for notifications)
-        virtual uint observerId() const = 0;
-
-        // commands from the Document to all observers
-        virtual void pageSetup( const QValueVector<KPDFPage*> & /*pages*/, bool /*documentChanged*/ ) {};
-        virtual void pageSetCurrent( int /*pageNumber*/, const QRect & /*viewport*/ = QRect() ) {};
-
-        // queries to observers
-        virtual bool canUnloadPixmap( int /*pageNum*/ ) { return true; }
-
-        // monitor changes in pixmaps (generation thread complete)
-        virtual void notifyPixmapChanged( int /*pageNumber*/ ) {};
-        virtual void notifyPixmapsCleared() {};
-};
-
-#define PRESENTATION_ID 1
-#define PART_ID 2
-#define PAGEVIEW_ID 3
-#define THUMBNAILS_ID 4
-#define TOC_ID 5
+class KPrinter;
 
 /**
  * @short The Document. Heart of everything. Actions take place here.
diff --git a/core/observer.h b/core/observer.h
new file mode 100644
index 000000000..9fb38300d
--- /dev/null
+++ b/core/observer.h
@@ -0,0 +1,48 @@
+/***************************************************************************
+ *   Copyright (C) 2005 by Enrico Ros <eros.kde@email.it>                  *
+ *   Copyright (C) 2005 by Albert Astals Cid <tsdgeos@terra.es>            *
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ ***************************************************************************/
+
+#ifndef _KPDF_DOCUMENTOBSERVER_H_
+#define _KPDF_DOCUMENTOBSERVER_H_
+
+#include <qvaluevector.h>
+#include <qrect.h>
+
+/** IDs for observers. Globally defined here. **/
+#define PRESENTATION_ID 1
+#define PART_ID 2
+#define PAGEVIEW_ID 3
+#define THUMBNAILS_ID 4
+#define TOC_ID 5
+
+/**
+ * @short Base class for objects being notified when something changes.
+ *
+ * Inherit this class and call KPDFDocument->addObserver( yourClass ) to get
+ * notified of asyncronous events (new pixmap generated, or changed, etc..).
+ */
+class KPDFDocumentObserver
+{
+    public:
+        // you must give each observer a unique ID (used for notifications)
+        virtual uint observerId() const = 0;
+
+        // commands from the Document to all observers
+        virtual void pageSetup( const QValueVector< class KPDFPage * > & /*pages*/, bool /*documentChanged*/ ) {};
+        virtual void pageSetCurrent( int /*pageNumber*/, const QRect & /*viewport*/ = QRect() ) {};
+
+        // queries to observers
+        virtual bool canUnloadPixmap( int /*pageNum*/ ) { return true; }
+
+        // monitor changes in pixmaps (generation thread complete)
+        virtual void notifyPixmapChanged( int /*pageNumber*/ ) {};
+        virtual void notifyPixmapsCleared() {};
+};
+
+#endif
diff --git a/part.cpp b/part.cpp
index 07b6508f9..d8af6cb59 100644
--- a/part.cpp
+++ b/part.cpp
@@ -21,6 +21,7 @@
  *   (at your option) any later version.                                   *
  ***************************************************************************/
 
+// qt/kde includes
 #include <qsplitter.h>
 #include <qpainter.h>
 #include <qlayout.h>
@@ -28,7 +29,6 @@
 #include <qvbox.h>
 #include <qtoolbox.h>
 #include <qpushbutton.h>
-
 #include <dcopobject.h>
 #include <kaction.h>
 #include <kdirwatch.h>
@@ -48,8 +48,8 @@
 #include <kxmlguiclient.h>
 #include <kxmlguifactory.h>
 
+// local includes
 #include "xpdf/GlobalParams.h"
-
 #include "part.h"
 #include "ui/pageview.h"
 #include "ui/thumbnaillist.h"
diff --git a/part.h b/part.h
index 91bc61db4..bdc5a0e2c 100644
--- a/part.h
+++ b/part.h
@@ -18,9 +18,8 @@
 
 #include <kparts/browserextension.h>
 #include <kparts/part.h>
-
+#include "core/observer.h"
 #include "dcop.h"
-#include "core/document.h"
 
 class QWidget;
 class QSplitter;
@@ -35,6 +34,7 @@ class KSelectAction;
 class KAboutData;
 class KPrinter;
 
+class KPDFDocument;
 class ThumbnailList;
 class PageView;
 class SearchWidget;
diff --git a/shell.cpp b/shell.cpp
index 6536114c4..dfb9f333a 100644
--- a/shell.cpp
+++ b/shell.cpp
@@ -33,7 +33,7 @@
 #include <kpopupmenu.h>
 #include <kparts/componentfactory.h>
 #include <kio/netaccess.h>
-#include <kmainwindowiface.h> 
+#include <kmainwindowiface.h>
 
 // local includes
 #include "shell.h"
diff --git a/shell.h b/shell.h
index 97434c67e..2dc7a60e5 100644
--- a/shell.h
+++ b/shell.h
@@ -73,8 +73,8 @@ namespace KPDF
 
     void optionsConfigureToolbars();
     void applyNewToolbarConfig();
-      void slotUpdateFullScreen();
-       void slotShowMenubar();
+    void slotUpdateFullScreen();
+    void slotShowMenubar();
 
   public slots:
       void openURL( const KURL & url );
diff --git a/ui/pageview.cpp b/ui/pageview.cpp
index beaf07614..d3dc16bd0 100644
--- a/ui/pageview.cpp
+++ b/ui/pageview.cpp
@@ -16,13 +16,13 @@
  *   (at your option) any later version.                                   *
  ***************************************************************************/
 
+// qt/kde includes
 #include <qcursor.h>
 #include <qpainter.h>
 #include <qtimer.h>
 #include <qpushbutton.h>
 #include <qapplication.h>
 #include <qclipboard.h>
-
 #include <kiconloader.h>
 #include <kurldrag.h>
 #include <kaction.h>
@@ -34,11 +34,14 @@
 #include <kimageio.h>
 #include <kdebug.h>
 
+// system includes
 #include <math.h>
 #include <stdlib.h>
 
+// local includes
 #include "pageview.h"
 #include "pageviewutils.h"
+#include "core/document.h"
 #include "core/page.h"
 #include "core/link.h"
 #include "core/generator.h"
diff --git a/ui/pageview.h b/ui/pageview.h
index caac20079..4c9fb7ca7 100644
--- a/ui/pageview.h
+++ b/ui/pageview.h
@@ -21,12 +21,12 @@
 
 #include <qscrollview.h>
 #include <qvaluevector.h>
-
-#include "core/document.h"
+#include "core/observer.h"
 
 class KURL;
 class KActionCollection;
 
+class KPDFDocument;
 class PageViewItem;
 class PageViewPrivate;
 
diff --git a/ui/presentationwidget.h b/ui/presentationwidget.h
index 0c7a7c4ec..211df139b 100644
--- a/ui/presentationwidget.h
+++ b/ui/presentationwidget.h
@@ -14,12 +14,15 @@
 #include <qpixmap.h>
 #include <qstringlist.h>
 #include <qvaluevector.h>
-#include "core/document.h"
+#include "core/observer.h"
 
-class PresentationFrame;
 class KToolBar;
 class QTimer;
 
+class KPDFDocument;
+class KPDFPage;
+class PresentationFrame;
+
 /**
  * @short A widget that shows pages as fullscreen slides (with transitions fx).
  *
diff --git a/ui/thumbnaillist.cpp b/ui/thumbnaillist.cpp
index 9b98d977c..ef8c2e4c5 100644
--- a/ui/thumbnaillist.cpp
+++ b/ui/thumbnaillist.cpp
@@ -18,6 +18,7 @@
 
 // local includes
 #include "thumbnaillist.h"
+#include "core/document.h"
 #include "core/generator.h"
 #include "core/page.h"
 
diff --git a/ui/thumbnaillist.h b/ui/thumbnaillist.h
index 83d8bb8e3..5147d5251 100644
--- a/ui/thumbnaillist.h
+++ b/ui/thumbnaillist.h
@@ -7,13 +7,13 @@
  *   (at your option) any later version.                                   *
  ***************************************************************************/
 
-#ifndef THUMBNAILLIST_H
-#define THUMBNAILLIST_H
+#ifndef _KPDF_THUMBNAILLIST_H_
+#define _KPDF_THUMBNAILLIST_H_
 
 #include <qscrollview.h>
 #include <qvaluevector.h>
 #include <qvbox.h>
-#include "core/document.h"
+#include "core/observer.h"
 
 class QTimer;
 class KActionCollection;
diff --git a/ui/toc.cpp b/ui/toc.cpp
index fcb1abcad..44d207fb4 100644
--- a/ui/toc.cpp
+++ b/ui/toc.cpp
@@ -13,8 +13,8 @@
 
 // local includes
 #include "toc.h"
-#include "core/page.h"
 #include "core/document.h"
+#include "core/page.h"
 
 // uncomment following to enable a 2nd column showing the page referred by
 // each tree entry
diff --git a/ui/toc.h b/ui/toc.h
index 8cdad1695..62376a7a0 100644
--- a/ui/toc.h
+++ b/ui/toc.h
@@ -7,12 +7,11 @@
  *   (at your option) any later version.                                   *
  ***************************************************************************/
 
-#ifndef TOC_H
-#define TOC_H
+#ifndef _KPDF_TOC_H_
+#define _KPDF_TOC_H_
 
 #include <klistview.h>
-
-#include "core/document.h"
+#include "core/observer.h"
 
 class TOC : public KListView, public KPDFDocumentObserver
 {