It's easy to cite LitCharts for use in academic papers and reports.
MLA
Arn, Jackson. "Guns, Germs, and Steel." LitCharts. LitCharts LLC, 26 Nov 2016. Web. 23 Jan 2021.
Chicago
Arn, Jackson. "Guns, Germs, and Steel." LitCharts LLC, November 26, 2016. Retrieved January 23, 2021. https://www.litcharts.com/lit/guns-germs-and-steel.