1. National Electronic Library for Health (NeLH) http://www.nelh.nhs.uk.
2. OMNI website http://omni.ac.uk.
3. NMAP website http://nmap.ac.uk.
4. Focusing Clinical Questions. Oxford Centre for Evidence Based Medicine Web site, http://cebm.net/focus_quest.asp.
5. Finding the Evidence for Practice: A Workbook for Health Professionals;Brettle,2003