Source Apportionment of Ambient Particulate Matter (PM) in Two Western African Urban Sites (Dakar in Senegal and Bamako in Mali) oleh Thierno Doumbia, Catherine Liousse, Marie-Roumy Ouafo-Leumbe, Seydi Ababacar Ndiaye, Eric Gardrat, Corinne Galy-Lacaux, Cyril Zouiten, Véronique Yoboué, Claire Granier