It's easy to cite LitCharts for use in academic papers and reports.
MLA
Florman, Ben. "Heart of Darkness." LitCharts. LitCharts LLC, 22 Jul 2013. Web. 28 May 2020.
Chicago
Florman, Ben. "Heart of Darkness." LitCharts LLC, July 22, 2013. Retrieved May 28, 2020. https://www.litcharts.com/lit/heart-of-darkness.