Juniper M, Le TK, Mladsi D. The epidemiology, economic burden, and pharmacological treatment of chronic low back pain in France, Germany, Italy, Spain and the UK: a literature-based review. Expert Opin Pharmacother. 2009 Nov 1;10(16):2581-92. doi: 10.1517/14656560903304063.
Earnshaw SR, Wilson MR, Dalal AA, Chambers MG, Jhingran P, Stanford R, Mapel DW. Cost-effectiveness of fluticasone propionate/salmeterol (500/50 microg) in the treatment of COPD. Respir Med. 2009 Jan 1;103(1):12-21.