APA (7th ed.) Citation

Wolff, E., & Sengel, P. El ser viviente.

Chicago Style (17th ed.) Citation

Wolff, Etienne, and Philippe Sengel. El Ser Viviente.

MLA (8th ed.) Citation

Wolff, Etienne, and Philippe Sengel. El Ser Viviente.

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