15.09.2003
Combined salmeterol and fluticasone in the treatment of chronic obstructive pulmonary disease: a randomised controlled trial
P. Calverley, R. Pauwels, J. Vestbo, P. Jones, N. Pride, A. Gulsvik, J. Anderson, C. Maden, for the TRISTAN (TRial of Inhaled STeroids ANd long-acting 2 agonists) Study Group
The Lancet, 2003; 361: 449-456