APA Style

Hadfield, S. et al (2019). Cara bersikap tegas dalam segala situasi = How to be assertive in any situation . New York: Aura publishing.

MLA Style

Hadfield, Sue. et al. "Cara bersikap tegas dalam segala situasi = How to be assertive in any situation". New York: Aura publishing, 2019. Text.