@unpublished{TUW-191334, author = {Alizadeh, Mahdi and Schuh, Harald and Schmidt, Michael}, title = {Spherical Harmonics and Chapman Profile Approach for Modeling The Electron Density}, year = {2010}, note = {poster presentation: International Beacon Satellite Symposium 2010, Barcelona, Spanien; 2010-06-07 -- 2010-06-11} }