[4] Stein S W, Myrdal P B, Gabrio B J, et al. Evaluation of a new aerodynamic particle size distribution measurements of solution meterred dose inhalers [J]. Aerosol Medicine, 2003, 16: 107-119.
[5] Peters T M, Leith D. Concentration measurement and counting efficiency of the aerodynamic particle sizer 3321 [J]. Aerosol Sci., 2003, 34(5): 627-634.