3Hussain M.An investigation of wind forces on three dimensional roughness Elements in a simulated atmosphedc boundary Layer flow.Sheffield,Yorkshire,England:Report BSS6,Department of Building Science,Faculty of Architectural Studies,Universities of Sheffield,1980.
4Kirchstetter T W.Controlled generation of black carbon particles from a diffusion flame and applications in evaluating black carbon measurement methods.Atmospheric Environment,2007,41:9.