Ahmed, Mohammed Jamaluddin, Mohammed Khorshed Ali, Muzammel Hossain, Shajahan Siraj, and Mohammed Aminul Ahsan. 2012. “Determination of Trace Metals in Air of Chittagong City-Bangladesh”. European Journal of Chemistry 3 (4):416-20. https://doi.org/10.5155/eurjchem.3.4.416-420.645.