Gardner, H. (1991). To open minds. Basic Books.
Chicago Style aipamenaGardner, Howard. To Open Minds. USA: Basic Books, 1991.
MLA aipamenaGardner, Howard. To Open Minds. Basic Books, 1991.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.
Gardner, H. (1991). To open minds. Basic Books.
Chicago Style aipamenaGardner, Howard. To Open Minds. USA: Basic Books, 1991.
MLA aipamenaGardner, Howard. To Open Minds. Basic Books, 1991.