APA引文

Ratzel,, F. (1989). History of mankind: Vol.1. Radha Publication.

Chicago Edition Citation

Ratzel,, Friedrich. History of Mankind: Vol.1. Delhi: Radha Publication, 1989.

MLA引文

Ratzel,, Friedrich. History of Mankind: Vol.1. Radha Publication, 1989.

警告：這些引文格式不一定是100％准確.