In-vitro measurement of aerosol generated by Respimat SMI penetrating through upper airwaysOndrej Misik, Frantisek Lizal, Milan Malý, Jakub Karas, Jan Jedelsky and Miroslav JichaEPJ Web Conf., 269 (2022) 01038DOI: https://doi.org/10.1051/epjconf/202226901038