World Health Organization. (2011). Atlas of headache disorders and resources in the world 2011. World Health Organization.
Chicago-Zitierstil (17. Ausg.)World Health Organization. Atlas of Headache Disorders and Resources in the World 2011. Geneva, Switzerland: World Health Organization, 2011.
MLA-Zitierstil (8. Ausg.)World Health Organization. Atlas of Headache Disorders and Resources in the World 2011. World Health Organization, 2011.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.