Comparison of the effects of nitric oxide, nitroprusside, and nifedipine on hemodynamics and right ventricular contractility in patients with chronic pulmonary hypertension. - Cockrill,B.A.; Kacmarek,R.M.; Fifer,M.A.; Bigatello,L.M.; Ginns,L.C.; Zapol,W.M. (Chest, 2001)