Authors: S I Rennard; W Anderson; R ZuWallack; J Broughton; W Bailey; M Friedman; M Wisniewski; K Rickard Journal: Am J Respir Crit Care Med Date: 2001-04 Impact factor: 21.405
Authors: Peter M A Calverley; Julie A Anderson; Bartolome Celli; Gary T Ferguson; Christine Jenkins; Paul W Jones; Julie C Yates; Jørgen Vestbo Journal: N Engl J Med Date: 2007-02-22 Impact factor: 91.245