APA (7th ed.) Citation

Sundberg, B. M., Sundberg, L., & Lee, P. (1981). Horizon. BBC Worldwide.

Chicago Style (17th ed.) Citation

Sundberg, Britt Marie, L. Sundberg, and Penelope Lee. Horizon. London, England: BBC Worldwide, 1981.

MLA (9th ed.) Citation

Sundberg, Britt Marie, et al. Horizon. BBC Worldwide, 1981.