World Health Organization. (2011). Atlas of headache disorders and resources in the world 2011. World Health Organization.
Chicago-viite (17. p.)World Health Organization. Atlas of Headache Disorders and Resources in the World 2011. Geneva, Switzerland: World Health Organization, 2011.
MLA-viite (8. p.)World Health Organization. Atlas of Headache Disorders and Resources in the World 2011. World Health Organization, 2011.
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