Upper gastrointestinal (UGI) tolerability of celecoxib, a COX-2 specific inhibitor, compared to naproxen and placebo. - Bensen,W.G.; Agrawal,N.M.; Zhao,S.Z.; Burke,T.A.; Zabinski,R.A.; Maurath,C.J.; Geis,G.S. (Arthritis Rheum, 1999)