1. Β-Blockers for the prevention of acute exacerbations of chronic obstructive pulmonary disease (βLOCK COPD): a randomised controlled study protocol. Issue 6 (7th June 2016) Authors: Bhatt, Surya P; Connett, John E; Voelker, Helen; Lindberg, Sarah M; Westfall, Elizabeth; Wells, J Michael; Lazarus, Stephen C; Criner, Gerard J; Dransfield, Mark T Journal: BMJ open Issue: Volume 6:Issue 6(2016) Page Start: Record Type: Journal Article View Content: Available online (eLD content is only available in our Reading Rooms) ↗