Authors: D A Campbell; G McLennan; J R Coates; P A Frith; P A Gluyas; K M Latimer; A J Martin; D M Roder; R E Ruffin; D Scarce Journal: Thorax Date: 1993-11 Impact factor: 9.139
Authors: W O Spitzer; S Suissa; P Ernst; R I Horwitz; B Habbick; D Cockcroft; J F Boivin; M McNutt; A S Buist; A S Rebuck Journal: N Engl J Med Date: 1992-02-20 Impact factor: 91.245
Authors: D A Campbell; P M Yellowlees; G McLennan; J R Coates; P A Frith; P A Gluyas; K M Latimer; C G Luke; A J Martin; R E Ruffin Journal: Thorax Date: 1995-03 Impact factor: 9.139