Yasmin, S, et al. “Efficacy of Salbutamol by Nebulizer Versus Metered Dose Inhaler With Home-Made Non-Valved Spacer in Acute Exacerbation of Childhood Asthma”. Mymensingh Medical Journal, vol. 21, no. 1, Nov. 2012, pp. 66-71, https://www.banglajol.info/index.php/MMJ/article/view/12514.