“An Experimental Study on Regulated and Unregulated Pollutants from a Spark Ignition Car Fuelled on Liquefied Petroleum Gas and Gasoline: Pollutants from LPG Gasoline Cars”. Biological Sciences - PJSIR, vol. 53, no. 4, June 2010, pp. 223-9, https://www.v2.pjsir.org/index.php/biological-sciences/article/view/463.