Butterworth, C. W. Ethical and political philosophy: Charles W. Butterworth. The Cambridge Companion to Arabic philosophy.(2006).
Chicago-viite (17. p.)Butterworth, Charles W. "Ethical and Political Philosophy: Charles W. Butterworth." The Cambridge Companion to Arabic Philosophy.(2006) .
MLA-viite (8. p.)Butterworth, Charles W. "Ethical and Political Philosophy: Charles W. Butterworth." The Cambridge Companion to Arabic Philosophy.(2006), .
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.