Bennett, Gaymon; Hewlett, Martinez Joseph; Peters, Ted; Russell, Robert John (2008). The Evolution of Evil (بالإنجليزية). Vandenhoeck & Ruprecht. pp. 301–302. ISBN:978-3-525-56979-5. Archived from the original on 2024-02-17.
Bennett, Gaymon; Hewlett, Martinez Joseph; Peters, Ted; Russell, Robert John (2008). The Evolution of Evil (بالإنجليزية). Vandenhoeck & Ruprecht. pp. 301–302. ISBN:978-3-525-56979-5. Archived from the original on 2024-02-17.