MQX-503, a novel formulation of nitroglycerin, improves the severity of Raynaud's phenomenon: A randomized, controlled trial. - Chung L; Shapiro L; Fiorentino D; Baron M; Shanahan J; Sule S; Hsu V; Rothfield N; Steen V; Martin RW; Smith E; Mayes M; et al. (Arthritis & Rheumatism, 2009)