8Weitzenblum,E,et al.Long-term oxygen therapy can reverse the progression of pulmonary hypertension in patients with chronic obstructive pulmonary disease. The American Review of Respiratory Disease . 1985
9Adamo IP,et al.The Cleveland clinic initial experience with transtracheal oxygen therapy. Respiratory Care . 1990
10Domingo C,et al.Hemodynamic followup in COPD with 24 hour liquid oxygen therapy through transtracheal catheter. Chest . 1991
