1. Cars O, Mölstad S, Melander A (2001) Variation in antibiotic use in the European Union. Lancet 357:1851–1853
2. WHO Collaborating Centre for Drug Statistics Methodology (Norway) (2002) Guidelines for ATC classification and DDD assignment. WHO Collaborating Centre, Oslo
3. WHO Collaborating Centre for Drug Statistics Methodology (Norway) (2002) ATC index with DDDs. WHO Collaborating Centre, Oslo
4. WHO Collaborating Centre for Drug Statistics Methodology (Norway) (1999) ATC index with DDDs. WHO Collaborating Centre, Oslo
5. Nordic Medico Statistical Committee (Denmark) (2001) Health Statistics in the Nordic Countries. Report 61, 2001. NOMESCO, Copenhagen