1. WHO. International Statistical Classification of Diseases and Related Health Problems. 10th Revision. Geneva, Switzerland: World Health Organisation, 2004.
2. World Health Organization. Production of ICD-11: The overall revision process. http://www.who.int/classifications/icd/ICDRevision.pdf (11 March 2015, date last accessed).
3. World Health Organization. Classifications: ICD Revision Topic Advisory Groups. http://www.who.int/classifications/icd/TAGs/en/index.html . (11 March 2015, date last accessed).
4. ICD-11 for quality and safety: overview of the who quality and safety topic advisory group
5. Glaser B , Strauss A . The Discovery of Grounded Theory . Chicago: Aldine Publishing Company, 1967.