Upper gastrointestinal tolerability of celecoxib, a cox-2 specific inhibitor, compared to naproxen and placebo. - Bensen,W.G.; Zhao,S.Z.; Burke,T.A.; Zabinski,R.A.; Makuch,R.W.; Maurath,C.J.; Agrawal,N.M.; Geis,G.S. (J Rheumatol, 2000)