Ratzel,, F. (1989). History of mankind: Vol.1. Radha Publication.
Chicago Style aipamenaRatzel,, Friedrich. History of Mankind: Vol.1. Delhi: Radha Publication, 1989.
MLA aipamenaRatzel,, Friedrich. History of Mankind: Vol.1. Radha Publication, 1989.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.