RT Journal Article SR Electronic T1 Safety of long-acting β-agonists: urgent need to clear the air remains JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP 3 OP 5 DO 10.1183/09031936.00163408 VO 33 IS 1 A1 R. Beasley A1 F. D. Martinez A1 A. Hackshaw A1 K. F. Rabe A1 P. J. Sterk A1 R. Djukanovic YR 2009 UL http://erj.ersjournals.com/content/33/1/3.abstract AB