APA (7th ed.) Citation

Bruun. (1957). The World in the twentieth century. D.C.Heath and company.

Chicago Style (17th ed.) Citation

Bruun. The World in the Twentieth Century. America: D.C.Heath and company, 1957.

MLA (9th ed.) Citation

Bruun. The World in the Twentieth Century. D.C.Heath and company, 1957.

Warning: These citations may not always be 100% accurate.