Hartley, C. W. S. (1977). Oil palm (2nd. ed.). Longman.
Chicago Style aipamenaHartley, C. W. S. Oil Palm. 2nd. ed. London: Longman, 1977.
MLA aipamenaHartley, C. W. S. Oil Palm. 2nd. ed. Longman, 1977.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.