1. Codeine phosphate in paediatric medicine
D.G. Williams, D.J. Hatch, R.F. Howard 
British Journal of Anaesthesia 
Volume 86, Issue 3, Pages (March 2001)
DOI: /bja/
Copyright © 2001 British Journal of Anaesthesia Terms and Conditions

2. Fig 1 World Health Organization analgesic ladder.
British Journal of Anaesthesia  , DOI: ( /bja/ )
Copyright © 2001 British Journal of Anaesthesia Terms and Conditions

3. Fig 2 The chemical structure of codeine.
British Journal of Anaesthesia  , DOI: ( /bja/ )
Copyright © 2001 British Journal of Anaesthesia Terms and Conditions

4. Fig 3 Metabolism of codeine.
British Journal of Anaesthesia  , DOI: ( /bja/ )
Copyright © 2001 British Journal of Anaesthesia Terms and Conditions