APA (7th ed.) Citation

Bramwell, A. R. S., Done, G., & Balmford, D. Bramwell's helicopter dynamics.

Chicago Style (17th ed.) Citation

Bramwell, A. R. S., George Done, and David Balmford. Bramwell's Helicopter Dynamics.

MLA (8th ed.) Citation

Bramwell, A. R. S., et al. Bramwell's Helicopter Dynamics.