Dupré, John: Humans and other animals. Oxford : Oxford ; New York : Oxford University Press 2002. Internet: https://books.google.de/books?id=_a9zDR6oDTYC&printsec=frontcover&dq=Humans+and+Other+Animals&hl=de&sa=X&ved=0ahUKEwi7rsj2q5rTAhWFtRQKHeWKDJkQ6AEIHDAA#v=onepage&q=Humans%20and%20Other%20Animals&f=false.