APA (7th ed.) Citation

Krebs Wilckens, R. (1961). Historia Universal. Zig-Zag.

Chicago Style (17th ed.) Citation

Krebs Wilckens, Ricardo. Historia Universal. Santiago: Zig-Zag, 1961.

MLA (9th ed.) Citation

Krebs Wilckens, Ricardo. Historia Universal. Zig-Zag, 1961.

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