diff --git a/src/core/resources/skeletonresource.h b/src/core/resources/skeletonresource.h
index 231ce97..2591ad1 100644
--- a/src/core/resources/skeletonresource.h
+++ b/src/core/resources/skeletonresource.h
@@ -1,74 +1,74 @@
 /*
  *  Copyright 2013  Andreas Cord-Landwehr <cordlandwehr@kde.org>
  *
  *  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) version 3 or any later version
  *  accepted by the membership of KDE e.V. (or its successor approved
  *  by the membership of KDE e.V.), which shall act as a proxy
  *  defined in Section 14 of version 3 of the license.
  *
  *  This program is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *  GNU General Public License for more details.
  *
  *  You should have received a copy of the GNU General Public License
  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 #ifndef SKELETONRESOURCE_H
 #define SKELETONRESOURCE_H
 
 #include "artikulatecore_export.h"
 #include "core/ieditablecourse.h"
 
 #include <QObject>
 
 class SkeletonResourcePrivate;
 class IResourceRepository;
 
 /**
  * @brief The SkeletonResource class is a decorator for EditableCourseResource
  */
 class ARTIKULATECORE_EXPORT SkeletonResource : public IEditableCourse
 {
     Q_OBJECT
     Q_INTERFACES(ICourse)
 
 public:
     static std::shared_ptr<SkeletonResource> create(const QUrl &path, IResourceRepository *repository);
     ~SkeletonResource() override;
 
     QString id() const override;
     void setId(QString id) override;
     QString foreignId() const override;
     void setForeignId(QString id) override;
     QString title() const override;
     void setTitle(QString title) override;
     QString i18nTitle() const override;
     void setI18nTitle(QString title) override;
     QString description() const override;
     void setDescription(QString description) override;
     std::shared_ptr<ILanguage> language() const override;
     void setLanguage(std::shared_ptr<ILanguage> language) override;
     QVector<std::shared_ptr<Unit>> units() override;
     QUrl file() const override;
     bool exportToFile(const QUrl &filePath) const override;
     std::shared_ptr<Unit> addUnit(std::unique_ptr<Unit> unit) override;
     bool sync() override;
     void updateFrom(std::shared_ptr<ICourse>) override;
     bool isModified() const override;
-    std::shared_ptr<IEditableCourse> self() const;
+    std::shared_ptr<IEditableCourse> self() const override;
 
 private:
     /**
      * Create course resource from file.
      */
     explicit SkeletonResource(const QUrl &path, IResourceRepository *repository);
     void setSelf(std::shared_ptr<ICourse> self) override;
     const QScopedPointer<SkeletonResourcePrivate> d;
 };
 
 #endif