A multicentre, randomized, placebo- and active-controlled trial comparing the efficacy and safety of topical ketoprofen in Transfersome gel (IDEA-033) with ketoprofen-free vehicle (TDT 064) and oral celecoxib for knee pain associated with osteoarthritis - Conaghan, P G; Dickson, J; Bolten, W; Cevc, G; Rother, M (Rheumatology (Oxford), 2013)