См.: Morgan, M.L. (2001), Classics of Moral and Political Theory, Cambridge, MA: Hackett Publishing Co. Процитировано в ст.: Nafstad, H. (2015), 'Historical, philosophical, and epistemological perspectives', in S. Joseph (ed.), Positive Psychology in Practice: Promoting Human Flourishing in Work, Health, Education and Everyday Life (2nd edition), Hoboken: Wiley.