Chaudhary, A., and Z. Hussain Iqbal. “Role Of Spacer Device In Improving FEV1 And PEFR In Asthmatic Patients”. Esculapio Journal of SIMS, vol. 7, no. 2, Aug. 2023, pp. 2-4, https://esculapio.pk/journal/index.php/journal-files/article/view/825.