Moradpour,Z , , Hesam,G , , Helmi_Kohnehshahri,M , , Bokharaei-Salim,F , , Pouyakian,M , and Zendehdel,R . "Investigating the Ventilation System of an Intensive Care Unit in the COVID-19 Crisis: A Study in a Hospital of Tehran, Iran", TANAFFOS (Respiration), 20, 3, 2021, 240-245.