An Efficacy and Safety Study to Compare Three Doses of BEA 2180 BR to Tiotropium and Placebo in the Respimat Inhaler. [clinicaltrials:NCT00528996]

An Efficacy and Safety Study to Compare Three Doses of BEA 2180 BR to Tiotropium and Placebo in the Respimat Inhaler. [clinicaltrials:NCT00528996]