Cita APA (7a ed.)

Hume, D. (1997). An enquiry concerning human understanding ; A letter from a gentleman to his friend in Edinburgh ; An abstract of a tratise of human nature. Hackett.

Cita Chicago Style (17a ed.)

Hume, David. An Enquiry Concerning Human Understanding ; A Letter from a Gentleman to His Friend in Edinburgh ; An Abstract of a Tratise of Human Nature. Indianapolis [etc.]: Hackett, 1997.

Cita MLA (9a ed.)

Hume, David. An Enquiry Concerning Human Understanding ; A Letter from a Gentleman to His Friend in Edinburgh ; An Abstract of a Tratise of Human Nature. Hackett, 1997.