Authors: Helgo Magnussen; Bernd Disse; Roberto Rodriguez-Roisin; Anne Kirsten; Henrik Watz; Kay Tetzlaff; Lesley Towse; Helen Finnigan; Ronald Dahl; Marc Decramer; Pascal Chanez; Emiel F M Wouters; Peter M A Calverley Journal: N Engl J Med Date: 2014-09-08 Impact factor: 91.245