El-Sheekh, M. M., & Hassan, I. A. (2020). Lockdowns and reduction of economic activities during the COVID-19 pandemic improved air quality in Alexandria, Egypt. Environ Monit Assess.
Chicago-tyylinen lähdeviittausEl-Sheekh, Mostafa M., ja Ibrahim A. Hassan. "Lockdowns and Reduction of Economic Activities During the COVID-19 Pandemic Improved Air Quality in Alexandria, Egypt." Environ Monit Assess 2020.
MLA-viiteEl-Sheekh, Mostafa M., ja Ibrahim A. Hassan. "Lockdowns and Reduction of Economic Activities During the COVID-19 Pandemic Improved Air Quality in Alexandria, Egypt." Environ Monit Assess 2020.
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