APA (7th ed.) Citation

World Health Organisation(Geneva), Lwanga, S. K., & Lemeshow, S. (1991). Sample size determination in health studies: A practical manual. WHO.

Chicago Style (17th ed.) Citation

World Health Organisation(Geneva), S. K. Lwanga, and S. Lemeshow. Sample Size Determination in Health Studies: A Practical Manual. Geneva: WHO, 1991.

MLA (8th ed.) Citation

World Health Organisation(Geneva), et al. Sample Size Determination in Health Studies: A Practical Manual. WHO, 1991.